

So this ship has an impressive 7500 tons of armor but the problem is that the ship is a mile and a half long. 7500 tons of armor is about 1000 cubic meters if it has the same density as steel. Such ship would be about an average 500 meters tall and 500 meters wide (picked these numbers because it has the smallest perimeter) such ship would have the surface area of
500x3.14x2000+250^2x3.14=3.3 million square meters of surface area.
1000/3,300,000=0.0003m or 0.4mm thick of armor
linky to ship
So one could really say foil thin armor

So my question is why don't they just use machine guns?