The problem with ground based lasers is that the atmosphere absorbs the laser if its not adjusted right frequency.
That is simply an engineering detail. The chemical oxygen iodine laser in YAL-1 does it by producing a laser beam tuned for iodine, which is barely measurable in the atmosphere. Free election lasers can be tuned to dozens of even better frequency windows.
Plus those mirrors are going to be Large and take damage over time from being in Orbit.
They are not that large, especially when folded, and would be light for their size. A single shuttle trip could transport 1 relay mirror or 2+ fighting mirrors, possibly more, per trip.
Everything takes damage over time, no matter where it is. One advantage of being in space is that you do not have to worry the damage from the 2 most destructive chemicals known to man – oxygen and water.
The most effective weapon available to used from space is and probably always will be a large mass excellerated at high speeds.
Depends on the target. It is like arguing about whether your company should have mortars or machine guns. -- The correct answer is you need some of both. :daz
Impactors are good for large hardened immobile targets, there is no way for a 8kps missile to see through the plasma surrounding it within the atmosphere, so moving targets are out. And the blast area is large, so you cannot use them when collateral damage is an issue.
The laser is the opposite, a precision weapon that work best on small targets that are no more than lightly armored, and the short flight time makes hitting a moving target possible. You can target a single person in a crowd and probably only injure 2 or 3 others in the process. A laser can destroy a car, but destroying a tank will be very difficult, and destroying a deep bunker is simply not practical. Do not expect to vaporize a city with a laser, but setting a lot of fires should be easy.
The biggest problem with ground based lasers is simple. They dont move.
No, they don’t. But they can be a very hard target, only the relay mirror has to be exposed on the surface, the lasers can be deep buried. And the orbital mirrors allow the laser to hit almost any point on the face of the earth that the orbital mirrors can see with little or no warning, and, if you are using free electron lasers, can keep firing as long as the electric grid is intact. :hul
He who controls the orbitals wins.
Another old quote, but still very true.