Also, if you can build a mirror to bounce the laser you can use that same mirror to protect the target. Not necessarily. The attacker controls the focal distan

Also, if you can build a mirror to bounce the laser you can use that same mirror to protect the target. Not necessarily. The attacker controls the focal distance of the laser. If they are using a mirror offensively, they can adjust the focal distance to ensure that flux is not destructively high at the location of the relay mirror, but is at the target. If you are trying to use the same mirror defensively, the attacker can simply consider that mirror to be a new armor target that needs to be destroyed before they can get at you, and adjust their focus to create unsurvivable flux at the mirror surface.