How many men would it take to invade and control a planet?

[Straha]

Inspired by my thread in ST.

We have a lot more evidence here, from the Clone Wars and on screen in ESB. Obviously keeping planets like Tatooine is effectively merely a matter of controlling the star port with a large enough garrison to make punitive expeditions as necessary. But for full scale invasions even the battle of Hoth, which was against a motley rebel force which was merely trying to buy time from the Imperials, seemed to require a sizable Imperial force. Similar with the Wookies in Kashyyk (I know I mis-spelled that,) only replace Imperial with Trade Federation. I don't know much of the Clone Wars series so perhaps there's more information there. And, perhaps, estimates could be made from the troop carrying capacity of Star Destroyers compared with known invasion fleet sizes.

Anyway, thoughts?

[Warsie]

Depends on planet. Core Worlds-especially city-worlds thousands of ships.

Rim worlds-5-10 maybe? 6 Imperators and the support ships could subjugate a rim world like Abridon.

[Enforcer Talen]

Well, 10 million can die in 1918 without changing the borders much. . . so with higher population and tech, I would expect hundreds of millions of troops.

[Adrian Laguna]

Depends a lot on the planet, the defenders, and the objectives. On average it would easily be hundreds of millions. For very densely populated, or extremely well defended, planets it's very likely that soldiers the invasion force would have to number in the thousands of millions. The logistical ramifications of such an enterprise are simply staggering.

[Ritterin Sophia]

Obviously keeping planets like Tatooine is effectively merely a matter of controlling the star port with a large enough garrison to make punitive expeditions as necessary.

Tatooine is probably one of the easier planets to keep controlled, IIRC, only a small band around the equator is habitable, so that cuts down on the number of cities and therefore garrisons.

I don't know much of the Clone Wars series so perhaps there's more information there. And, perhaps, estimates could be made from the troop carrying capacity of Star Destroyers compared with known invasion fleet sizes.

Each Acclamator-class carries 1,600 troops, after Geonosis, the Republic ordered another thousand Acclamators, that's about half of Travissties 3 million already, then add in that there were even larger scale Acclamator variants which eventually became the Star Destroyers, simply put, the Republic has a shit load more than what some authors would lead you to believe. Grievous stated he had quintillions of droids (We'll say 5), let's be stupendously rediculous and say 100 (Realistically I'd say 10-20, with twenty stretching it) Battle Droids for one clone, that would require at least 50 quadrillion (500-250 quadrillion clones).

[MKSheppard]

Keep in mind that the Clone/Stormtroopers can exert battlefield control over a much larger area than normal troops; plus they have all that Force XXI situational awareness stuff times 1,000 in their helmets.

I'd say a few thousand can hold a world like Tatooine; the Stormtrooper presence didn't seem to be oppressive, even on the world's main spaceport, Mos Eisley.

For a large scale world, probably a million or two troops; with expansion to 10+ or more million troops if it's a heavily developed world or if it has significant defenses + armed forces

If it's coruscant, forget about swarming the planet with troops. Just send 10-25 million troops in and use orbital fire support heavily.

[Karmic Knight]

Well, 10 million can die in 1918 without changing the borders much. . . so with higher population and tech, I would expect hundreds of millions of troops.

Bad Example, in WW1 the defensive tech was higher than the offensive strategy. The tactic popular was to run thru no mans land while trying not to step on landmines and dodging machinegun fire. I don't see any leap between the offesne at such a disadvantage. But I could be wrong.

[Pablo Sanchez]

Probably the most critical advantage of an invading military in Star Wars is their control of the high ground, meaning supremacy in space--a planetary assault presupposes this, because no invasion landing could be realistically effected without it. This results in an insurmountable advantage in firepower and mobility.

Heavy orbital fire would be used to overwhelm fixed defenses and perform interdiction missions on the immense scale, i.e. preventing one end of a continent from helping the other. Space fighters deployed from orbit could then establish control of the airspace (again, orbital support would render defending aerospace fighters at an immense disadvantage) and perform more precise aerial attack on troops and infrastructure. This would make it impossible for defending forces to move without being sliced up from the air, and any forces that dug in and stayed immobile could be located by aerial and orbital reconnaissance and annihilated by precise orbital strikes.

The only way for the defenders to survive would be to fortify himself in locations that the attackers would prefer not to destroy, cities and the like. At the same time, however, these fortified cities would be isolated from one another and vulnerable to piecemeal assault.

This, together with the unprecedented mobility afforded by arbitrarily cheap space transport operations, would allow comparatively small forces to control an Earth-type world. Any figure I would name would be quite arbitrary, but 10-50 million would probably be sufficient, depending on how many civilian casualties the assaulting force is willing to cause. Obviously if they are obsessed with preventing collateral damage and civilian deaths they will need to cut back on orbital firepower and thus ground-pounders will have to pick up the slack. The most manpower intensive stage of the battle would probably be the post-battle occupation and anti-partisan activities, for which the advantages of mobility, and aerospace firepower are most minimized.

A city-world like Coruscant is a completely different proposition, because of the population and fortresslike terrain. As Sheppard says, the most efficient way to take such a planet would be overwhelming orbital bombardment in support of an inch-by-inch corridor slog. This would render most of the planet useless and cause innumerable civilian casualties. The alternative would be to surgically destroy enemy strongpoints and attack the planet with literally tens of billions of men, incurring immense casualties on the way.

[CaptHawkeye]

A ground attack on a city scape world like Coruscant is to me, a non option. If i'm trying to capture the planet, BDZing it doesn't help at all. Thus, it may be better to simply blockade it and order the enemy to surrender or suffer from mass starvation and famine.

Of course if i'm trying to destroy it, then BDZ all the way. But again, destroying what you are attempting to capture is not a great idea, unless you're the crew of Voyager.

[MKSheppard]

And pablo pretty much expounded all my thoughts on Star Wars troops.

People seem to want operations involving hundreds of millions of troops just so they can justify absurdly huge armies, forgetting that Star Wars has a massive firepower advantage and situational awareness advantage over what we're used to.

You can have the equivalent of the hiroshima bomb delivered with precision and cheapness from orbit, not to mention all the supporting stuff like TIE Fighters and TIE Bombers; a concussion missile is what, 40-50 kt?

Also, look at the standard weapons loadout for a stormtrooper; I believe a common blaster pack for the E-11 holds something like 200-300 rounds of shots; that means that a stormtrooper with the standard 5-6 extra magazines has on average of 2,750 rounds available to him; and each shot is the rough equivalent of a .50 caliber round from it's fragmentation effects on concrete/tightly packed dirt, plus it's "insta kill" kapability of even armored troops, as opposed to today's battle loadout of only 150 rounds for modern troops.

In effect, Star Wars has traded manpower for absurd quantities of firepower.....which is EXACTLY what the Germans did in WWI when they reorganized their divisions; by losing a couple thousand men, but adding more machine guns to maintain the equivalent level of firepower.

[PainRack]

Probably the most critical advantage of an invading military in Star Wars is their control of the high ground, meaning supremacy in space--a planetary assault presupposes this, because no invasion landing could be realistically effected without it. This results in an insurmountable advantage in firepower and mobility.

Your opponent will similarly have such heavy firepower.

Even in a nuclear environment, it was assumed that battles would be fought by small, dispersed units ranging over large areas. While this would cut down on the number of troops, the need to cover an entire planet

Heavy orbital fire would be used to overwhelm fixed defenses and perform interdiction missions on the immense scale, i.e. preventing one end of a continent from helping the other.

One word. Shields. A tactical shield like Hoth allows for fixed defences that require a superior force to overwhelm. If such fixed defences also contain ASAT weapons like turbolasers , they can also contest space forces.

Space fighters deployed from orbit could then establish control of the airspace (again, orbital support would render defending aerospace fighters at an immense disadvantage) and perform more precise aerial attack on troops and infrastructure. This would make it impossible for defending forces to move without being sliced up from the air, and any forces that dug in and stayed immobile could be located by aerial and orbital reconnaissance and annihilated by precise orbital strikes.

Mobile, dispersed forces neccesary to cover an entire planet will still require troops in the tens of thousands. This ignores the logistic requirements of supporting those forces, which can be hidden and concealed from space observation.

There has to be a limit on firepower. While the destruction of the Ubese tactical weapons stockpile rendered the planet inhabitable, those weapons were considered to be banned by the Republic.

[Nieztchean Uber-Amoeba]

The only way to make an assault on a city-planet work without rendering the planet useless would be to completely blockade it from space (possibly requiring hundreds of ships) and set down skyhooks and theatre shields to capture a few vital installations - centres of government, the spaceport, any media or broadcasting stations- and wait for surrender as mass starvation sets in.

[Jim Raynor]

Each Acclamator-class carries 1,600 troops, after Geonosis, the Republic ordered another thousand Acclamators, that's about half of Travissties 3 million already

Correction: Each Acclamator carries 16,000 troops, so 1,000 of them would hold more than 5 times the number of troops as Traviss's bullshit 3 million.

[MKSheppard]

One word. Shields. A tactical shield like Hoth allows for fixed defences that require a superior force to overwhelm. If such fixed defences also contain ASAT weapons like turbolasers , they can also contest space forces.

But you can't do anything really with your shields up. You have to drop them to let out ships as well. Which means that if you raise your shields, you've just blockaded yourself.

[Noble Ire]

One word. Shields. A tactical shield like Hoth allows for fixed defences that require a superior force to overwhelm. If such fixed defences also contain ASAT weapons like turbolasers , they can also contest space forces.

But you can't do anything really with your shields up. You have to drop them to let out ships as well. Which means that if you raise your shields, you've just blockaded yourself.

Indeed. Planetary and large theater shields are only really effective if the besieged world has reinforcements coming (or, in the Rebel's case, if one simply intends to abandon the world); even if the defensive weaponry of the planet could somehow shoot through its own shielding, which it can't, the invaders would eventually be able to overwhelm the defending force.

[Ritterin Sophia]

Each Acclamator-class carries 1,600 troops, after Geonosis, the Republic ordered another thousand Acclamators, that's about half of Travissties 3 million already

Correction: Each Acclamator carries 16,000 troops, so 1,000 of them would hold more than 5 times the number of troops as Traviss's bullshit 3 million.

Sorry, my apologies, the only book I have that gives the number of troops is the SWRPG Revised Core Rulebook and I leant it out.

[PainRack]

But you can't do anything really with your shields up. You have to drop them to let out ships as well. Which means that if you raise your shields, you've just blockaded yourself.

Shields to defend fixed positions, not shields protecting your airbases. Furthermore, SW has the ability to raise and lower shields in split seconds, thus negating this issue.
As long as such shields exist, a large field army can be maintained. Even if the army is dispersed to fight as in a nuclear war, such positions force the invader to commit larger forces just to overrun them.

Indeed. Planetary and large theater shields are only really effective if the besieged world has reinforcements coming (or, in the Rebel's case, if one simply intends to abandon the world); even if the defensive weaponry of the planet could somehow shoot through its own shielding, which it can't, the invaders would eventually be able to overwhelm the defending force.

Defensive weaponry do appear to be capable of shooting through shielding, at least they do in Thrawn siege.

[MKSheppard]

Shields to defend fixed positions, not shields protecting your airbases.

So your airbases are cratered from orbit by ISD turbolaser fire.

Furthermore, SW has the ability to raise and lower shields in split seconds, thus negating this issue.

Too bad the Empire has sensors and weapons specifically designed to fire in such absurdly short periods of time; e.g. torpedo spheres. And it's kind of hard to turn your shield on and off in split seconds, when you're dealing with ships entering and exiting. You have to turn it off well in advance of the ship, so it doesn't hit it; and well after the ship leaves to avoid bisecting the ship.

As long as such shields exist, a large field army can be maintained.

Except it can't do jack and shit except sit there.

Even if the army is dispersed to fight as in a nuclear war, such positions force the invader to commit larger forces just to overrun them.

Or we just wait for them to run out of food, or simply turbolaser the area AROUND the shield; and reduce it to a river of lava and cook them inside their shield.

[phongn]

Too bad the Empire has sensors and weapons specifically designed to fire in such absurdly short periods of time; e.g. torpedo spheres. And it's kind of hard to turn your shield on and off in split seconds, when you're dealing with ships entering and exiting. You have to turn it off well in advance of the ship, so it doesn't hit it; and well after the ship leaves to avoid bisecting the ship.

The shield at Hoth seemed to work quite well in precision timing.

[MKSheppard]

The shield at Hoth seemed to work quite well in precision timing.

We really don't know how long the shield was up or down.

[Stark]

The EU has shields reactivated behind inbound ships so fast a tailing ship (a few hundred meters behind) strikes it and is destroyed. Where's the evidence for slow shield toggling? They open holes for their bullets for christs sake.

[PainRack]

So your airbases are cratered from orbit by ISD turbolaser fire.

And as I said, if such fixed positions are protected by ASAT weapons like turbolasers, they can contest space superority. The Hoth tactical shield was powerful enough that 5 ISDs and a Executor could not bring it down.

Too bad the Empire has sensors and weapons specifically designed to fire in such absurdly short periods of time; e.g. torpedo spheres.

No. Torpedo spheres are meant to scan and analyze weak spots in a planetary shield then bombard it. This weakens the shield to the extent that other assault craft can exploit "holes".

Not destroy targets in such split seconds. If such technology was widely available, during the 5th Fleet exercise at Bathomir, they would not have to rely on blind luck and density of fire to destroy the shield protecting the gun.(Before the storm)

And it's kind of hard to turn your shield on and off in split seconds, when you're dealing with ships entering and exiting. You have to turn it off well in advance of the ship, so it doesn't hit it; and well after the ship leaves to avoid bisecting the ship.

Except that the Rebels did do so for the transports leaving Hoth such that no enemy interceptors could enter. Furthermore, you're too fixated on this idea of airbases. My point was that tactical shields allow for fixed defences that will require a larger, superior ground force to overwhelm. As long as the defender has shields that can shrug off fire by the likes of Death Squadron, a large field army can exist and pose a tactical threat.

Except it can't do jack and shit except sit there.

Enough fixed positions containing turbolasers, missiles and the like and you force opponents to have to dedicate assets to blow them up. Which will thus increase the number of ground forces required.

Also, Naboo shows us that tactical shields can be portable. There is no reason to assume that SW field armies cannot deploy a portable shield that's powerful enough to withstand bombardment by frigates. There also exist mobile ASAT weapons such as the Loronar turbolasers.

Or we just wait for them to run out of food, or simply turbolaser the area AROUND the shield; and reduce it to a river of lava and cook them inside their shield.

Forcing a siege is the exact purpose of fixed defences. If you're overly reliant on space forces to conduct such a siege, you're fixing a large space force to a planet, allowing your own space forces to recover and either overwhelm the enemy fleet or attack other targets of oppurtinity.

As for the second, a shield system that can rapidly decant the heat from turbolasers bombardment should contain some form of environmental systems to allow defenders to survive.


If an Outer Rim world settled by religious exiles can obtain carrack cruisers for their defence, there is no reason to believe that an intergrated space/ground defence will be extensive enough that a large field army is required to invade it.

[Pablo Sanchez]

Your opponent will similarly have such heavy firepower.

No, he won't. By virtue of being under spaceborne attack, the defender on the planet is cut off from reinforcement, while the attack can assemble resources from the rest of the galaxy very rapidly by use of hyperdrive. The attacker can draw on the resources of multiple planets, while the defender has only what is at hand.

Moreover, simple geometry prevents the defender from bringing his firepower to bear effectively; the attacker has the high ground from orbit, while the horizon allows the defender to use only a very small portion to affect the ground battle.

Even in a nuclear environment, it was assumed that battles would be fought by small, dispersed units ranging over large areas. While this would cut down on the number of troops, the need to cover an entire planet.

As I said, ground-based turbolasers would have only minimal capacity to affect the land campaign. The defender would also be constrained by his desire to not unduly damage his home. He has to live there afterwards if he wins, whereas the attacker is likely to be less concerned.

But the real reason that your WWIII example doesn't work is because of the power of SW orbital observation. With their level of technology, they would almost certainly have the ability to observe movements of even very small forces, and any such forces moving in the open would be immediately annihilated. Meanwhile, the first act of the attacker would necessarily be the trivially easy operation of clearing the planetary orbit of any satellites or installations capable of offering this kind of observation to the defender. Whereas in WWIII NATO and WARPAC forces would be on similar observational footing, the defender in our scenario is blind and the attacker can see everything.

The attacker's superiority in firepower and his ability to see where it would be most effectively applied forces the defender into immobile fortification, either behind planetary shielding or by hiding in subterranean fortresses. These forces are incapable of maneuver and are thus incapable of affecting the course of the campaign. Doubly so for those not protected by shields, because even the direst earthworks are a joke against turbolasers--those forces can't even shoot for fear of destruction.

One word. Shields. A tactical shield like Hoth allows for fixed defences that require a superior force to overwhelm.

The problem is that these fixed fortifications are immobile, while a fleet is mobile. Thus the course of a brush war in Star Wars (say, one small confederation of systems against another) would probably proceed like this.

1. Space battle, either proceeding as a decisive engagement that leaves one side in control early, or as a drawn-out attritional affair with the same end result but a longer duration. (Remember that in SW unlike earthly naval engagements, there aren't any protected anchorages; the WWI performance of the Hochseeflotte can't be mimicked.)
2. The victorious side interdicts the commerce of the loser, cutting the lines of communication between the loser's planets.
3. The victor of the space battle concentrates overwhelming force over each enemy planet in its turn. The attacking fleet is concentrated and represents the resources of a whole confederation, while the planetary defenses are only made up of contributions from the defending planet.

Obviously it would be possible for the defending group to have concentrated immense defense expenditures on a single planet (e.g. the capital) but this would strip other planets of these resources. Likewise, its possible for the defender to have completely ignored a mobile fleet and concentrated entirely on fixed defenses--which, considering the likely relative cost of mobile space forces and fixed defenses, and assuming roughly equal (small on a SW scale) national resources, would probably make the planets all but impregnable. In that case the war would have to be an economic blockade which would likely take a long time but still end in victory.

Of course, on a larger, galactic scale, defensive concentration would be useless because of the immense fleets that could be concentrated on any single target. Only a victory in space could secure safety.

If such fixed defences also contain ASAT weapons like turbolasers , they can also contest space forces.

A land invasion would presuppose a siege campaign against orbital defenses which, given time, would be irresistible. It would be superficially similar to the medieval siege practice of methodically opening breaches in walls in preparation for an overwhelming assault. The idea that the highly limited arsenal of fixed planetary defense turbolasers could "contest" space forces is ludicrous and is not supported by any canon literature. These guns can cause damage to besieging forces and even drive off raiding enemies, but to a determined attack in strength, they're only an annoyance.

Also, barring exceptionally wealthy planets like Coruscant, shields and fixed guns will only cover a very small portion of a planet--a few key cities and installations. These cities can then be isolated from one another by setting up a large free-fire zone around each, which is scorched by bombardment, and then picked off piecemeal as with Hoth.

Mobile, dispersed forces neccesary to cover an entire planet will still require troops in the tens of thousands. This ignores the logistic requirements of supporting those forces, which can be hidden and concealed from space observation.

Why must the entire planet be covered by dispersed forces? The defender will be limited to those strongpoints he can defend with shields, the rest of the planet is completely at the mercy of orbital firepower and effectively irrelevant. If one captures all the strategic objectives, the number of enemies hiding out in tunnels matters not one whit, because those forces are a mass of individual units. If they maneuver, it must be done in units small enough to remain unseen or to present unappealing targets for bombardment--units too small to meet the attacker in decisive battle. If they are to be large enough to fight, they can't move without revealing themselves, and in any case they would be destroyed shortly after engaging anyway. Attacking probes that met strongpoints not protected by shields would break contact and call down the guns.

There has to be a limit on firepower. While the destruction of the Ubese tactical weapons stockpile rendered the planet inhabitable, those weapons were considered to be banned by the Republic.

Defending mobile forces could easily be annihilated by bombardment of an environmentally friendly firepower, especially considering the likely "cleanup" capacity of the SW civilization. A brief burst of 10 kiloton light turbolaser bolts landing in the middle of a corps-sized formation would turn it into hamburger and the sun would still rise in the morning. After a long campaign of this, the planet would probably be a mess, but uninhabitable? Unlikely.

As I said above in the example about Coruscant, if one opts to use less firepower it simply means one must use more manpower. The essential problem for the defender is the same. The advantages of space-borne mobility and firepower on both the strategic (in space) level, and on the tactical (planetwide) level allow the attacker to cut up the defender into penny-packets. He'll eat them one at a time in Hoth-style attacks.

[MKSheppard]

And as I said, if such fixed positions are protected by ASAT weapons like turbolasers, they can contest space superority. The Hoth tactical shield was powerful enough that 5 ISDs and a Executor could not bring it down.

Except that such shields are not uber wonders.

From To Conquer a World by WEG:

The first and most useful task you can perform is battling a planetary shield. These devices can reach full strength in only a few minutes. They consume energy at very high rates and are expensive to leave on all the time. They are usually only turned on when hostile forces arrive. If you can destroy a planetary shield generator in the few minutes it takes to fully raise the shield itself, your mission and the army's mission will be far easier.

No. Torpedo spheres are meant to scan and analyze weak spots in a planetary shield then bombard it. This weakens the shield to the extent that other assault craft can exploit "holes".

Not destroy targets in such split seconds. If such technology was widely available, during the 5th Fleet exercise at Bathomir, they would not have to rely on blind luck and density of fire to destroy the shield protecting the gun.(Before the storm)

Wrong.

Wrong.

WRONG.

From the Imperial Sourcebook:

The Torpedo Sphere, a dedicated siege platform, is designed to accomplish one mission - to knock out a planet's shields. Planetary shields, whether full or partial, protect a world from orbital bombardment. It takes a lot of troops to assault a planet. It is easier and far less expensive to simply pound a planet into submission with the weapons of a Star Destroyer. But planetary shields prevent this.

The Torpedo Sphere is a miniature Death Star, covered with thousands of dedicated energy receptors (DERs) designed to analyze shield emissions. Planetary shields are never uniformly even. They experience power anomalies and energy fluctuations just like other mechanical devices. The Torpedo Sphere parks in orbit around a planet and trains its DERs upon the world to search for weak points in the shielding. These weak points rarely exceed more than a 20 percent power drop, but this is enough for the Torpedo Sphere to bring down the shields.

The Sphere contains 500 proton torpedo tubes arranged in an inverted conical formation. Surrounding these tubes are 10 heavy turbolaser batteries. The actual destruction of a planet's shields is simple. The Torpedo Sphere arrives and analyzes the shields. It finds both the weak points and the location of the planet-bound shield generators. The Sphere then fires a salvo of torpedoes that knock a hole in the shield (at a weak point), followed by blasts from the turbolasers to destroy the generators. Then the bombardment of the planet can begin.

That is the quick version. In reality, it takes almost a hundred heavy weapons technicians to coordinate the tube launches. The target area rarely exceeds a six meter square. The hole this produces is actually a power surge that only lasts a few microseconds. If the turbolasers have not made their shots in this time, the process must start all over again.

The most difficult part of the entire process is determining exactly where the shield generators lie. Sensors cannot penetrate full planetary shields, so the crew of the Sphere must study the power waves within the shield to determine where the initial power is coming from.

There are only six Torpedo Spheres currently in service. They perform only one function, but it is an important one in these times of open rebellion.

Except that the Rebels did do so for the transports leaving Hoth such that no enemy interceptors could enter.

Because there were NO enemy interceptors in place, and many ships were out of place in their assigned positions.

From To Conquer a World by WEG:

"Coming out of hyperspace too close to the system forced the Star Destroyers to rush quickly to their assigned positions and they had little time to deploy proper fighter escort. Though some vessels had time to deploy fighters, many chose not to, sadly thinking that they so badly outclassed the Rebels on Hoth that there was no need for fighter support.

"As you can see here on the holo, when the first Rebel transport escaped there were still several vessels that had not even reached their assigned positions. Here you can see that the Victory-class Star Destroyer Firewind is far from its assigned position. These are the kinds of errors that can be expected when orders are hastily prepared and hastily executed."

Furthermore, you're too fixated on this idea of airbases. My point was that tactical shields allow for fixed defences that will require a larger, superior ground force to overwhelm.

No they won't. Not with the firepower level thrown around in SW. When the standard LIGHT missiles fired by TIE Bombers, etc are rated at 40-50 kilotons, it requires an absurd amount of fortifications to resist them. Oh sure, you can give each little brigade in your army a tactical shield rated to defeat that firepower, but how long will the fuel you need to run the tactical shield last?

As long as the defender has shields that can shrug off fire by the likes of Death Squadron, a large field army can exist and pose a tactical threat.

Except that large field army is quite vunerable to the firepower thrown around in Star Wars. And secondly, if the only thing the field army can do is just SIT there, then what is the point of the field army in the first place, except for sucking up precious manpower?

Enough fixed positions containing turbolasers, missiles and the like and you force opponents to have to dedicate assets to blow them up. Which will thus increase the number of ground forces required.

Too bad that there is an absurd amount of firepower available in Star Wars. And for fortifications to actually be useful against them, they have to be capable of resisting them...

Also, Naboo shows us that tactical shields can be portable. There is no reason to assume that SW field armies cannot deploy a portable shield that's powerful enough to withstand bombardment by frigates.

And what about the fuel to run said shields? Or do star wars armies have magical zero point energy production?

There also exist mobile ASAT weapons such as the Loronar turbolasers.

Wrong. Imperial Sourcebook says:

Ground installed [Loronar] System Is are usually encased in pure permacite and powered by a boron fission reactor. Each reactor is capable of powering a number of guns, so a single reactor is usually connected to multiple turbolaser emplacements. These multiple emplacements, called "hives," often share an underground system of living quarters or at the very least have a tunnel network leading back to the main base or city they are protecting.

The biggest drawback to the System I is its tendency to overheat. Poor coolant restrictor circuits allow gunners to fire up to 20 rapid shots using sustained fire. However, at this rate most gun batteries experience emergency shutdown after just five or six shots. Green gunners, in battle for the first time, often lose sight of their thermal monitors with predictable but often tragic results. A gun which experiences emergency shutdown can be out of service in-definitely, depending on the external weather conditions.

Forcing a siege is the exact purpose of fixed defences. If you're overly reliant on space forces to conduct such a siege, you're fixing a large space force to a planet, allowing your own space forces to recover and either overwhelm the enemy fleet or attack other targets of oppurtinity.

Except that you don't need a quite powerful space force to conduct a siege and destroy a planet.

From the Imperial Sourcebook

A full troop or battle squadron packs enough firepower to subjugate any system not protected by a equivalent fleet; no ground defense yet devised is sufficient to hold off a determined attack from these elements of the Navy.

...

Battle squadrons contain an Imperial-class Star Destroyer. There are other ships, but they matter little in the configuration. In addition to the Star Destroyer there are at least three lines, two attack and one pursuit line, for an average of 18 ships. If there is some system in the Empire that must be repressed, some force which must be run down, a battle squadron is the force of choice. Sending a battle squadron on a mission is the Navy’s way of showing that the job is of utmost importance.

Troop squadrons have two troop lines, an attack line, and a skirmish line for an average of 25 to 30 vessels. A troop squadron is most often used as a transfer point for Army units, reinforcing or reorganizing the Army complement of other squadrons. These transfers are usually conducted in deep space where there is little chance of interference. If a troop squadron shows up within a system, there is certainly something big happening.

Bombard squadrons have two torpedo lines, a skirmish line, and a pursuit line, for an average of 20 to 28 vessels. Bombard squadrons are assigned to worlds which have rebelled successfully and have organized a large surface military which would take far too long to defeat. Imperial commanders, pressed on so many planets, often deploy bombard squadrons in less severe circumstances.

Wow, I guess the Empire's going to have to really scrape the barrel for on average 30 ships, when the average sector group has 1,600 combat starships and the Empire has at it's control thousands of sector groups.

As for the second, a shield system that can rapidly decant the heat from turbolasers bombardment should contain some form of environmental systems to allow defenders to survive.

Now you're just reaching here.

[MKSheppard]

I had some thoughts on what a Coruscant campaign would look like.

Obviously fighting to seize the ENTIRE planet in a stalingradesque battle is pointless and futile. What you're really after is control of the Governmental complexes; such as the old Jedi Temple, Senate Complex, and whatever stuff that's good for prestige, since a lot of political power in SW comes from whoever is controlling the apparatus and trappings of political power.

However, in order to seize just the government complexes is going to require you to seize spaceports nearby, and wherever the environmental systems on Coruscant are; because:

1.) You need to support your troops in the government complex.

2.) It would look stupid if you finally secured the Old Senate Building after 6 months of block to block fighting, and then the weather in that section changes to something absurd like torrential acid rains or subzero temperatures, or the oxygen levels go down to low low levels.