"The Killing Star" - R-bombs and interstellar genocide

[Borgholio]

It'd be more of an issue of focus than power, for a laser. No matter how much energy you pump into a laser beam, over the course of dozens of lightyears the beam will spread out and become diffused. Even if you managed to focus a pinpoint laser over dozens of lightyears, it wouldn't be able to pump THAT much energy into the target...assuming you can even aim accurately enough to hit it. An RKV at least can be steered by thrusters and an onboard guidance system as it approaches the target.

[Simon_Jester]

I have a very hard time visualizing a combination of lasers that could be used effectively to focus the required energies over interstellar distances. I'm not sure what you'd need to do, but it'd be impressive.

Interstellar lasers are really good choices (surprisingly energy-efficient) for long range communications. But as an attack mode... I don't know.

[Jerry the Vampire]

Oh yeah, as I said it would be difficult (understatement of they year? Lol) but if you could do it you don't have to worry that it would almost certainly be intercepted.