Another example, remember the “Airborne Laser” program (Boeing 747 mounted)...max range about 185 miles, power output 1 megawatt...weight of airborne laser & it’s power supply 121,000 pounds. Geostationary orbit height 22,000 miles, so an over 100 megawatt laser needed?? Even in LEO (1000 miles) then a 5 megawatt laser needed. Best solid state lasers nowadays produce about 1,000 watts per 77 pounds of weight. Not enough Falcon 9 Heavy or Delta 4 Heavy rockets available for that!
https://en.wikipedia.org/wiki/Boeing_YAL-1
https://foxtrotalpha.jalopnik.com/the-airborne-laser-may-rise-again-but-it-will-look-very-1724892313
~~~~~~~~~~~~~~~
As we in engineering & science say, "That's about the size of it!" ;-)
The basic unit of measure for any beam weapon is Power Density on target. (i.e. watts/sq. cm.)
To overcome the inverse square law, that infers hellacious power (and power supply) -- and/or -- unheard-of collimation and focusing.
For simple ground attack, it's more "throw-weight-economical" to deploy kinetic weapons (e.g "Rods from God") than to deploy space-based DEWs.
TXnMA