Not all military projects are weapons and bombs. Some times they are logistical in nature. Sometimes, they are energy related.
Space-based solar power satellites (SPS) have been a staple of science fiction since the 1970s. Folks realized back around the Apollo program the
Earth's atmosphere would not be in the way of collecting solar power: the earth's atmosphere reflects 40% of the light from the sun. /And/ the
solar power satellites could also overcome one of the fundamental problems with solar power systems on Earth: orbits could be tailored so the solar
panels would /always/ be in sunlight unlike on Earth where the sun rises and sets as the Earth rotates, leaving the solar power system useless during
certain times of that day. However, there are nontrivial issues historically.
The first is that launch costs have been extremely high. $10,000/lb to low earth orbit crippled the chances of placing solar panels in space and
getting any reasonable ROI. While this has come down significantly, the costs still make an SPS unable to compete with a terrestrially placed solar
power system. $10,000/lb is more than enough money increase the terrestrial solar power system many times over, more than making up for the limited
time the sun is in the sky. Musk and Bezos are driving the launch industry to vastly reduce their costs. The day of $100/lb are still a long ways
off even so.
Additionally, the solar power sats would be physically constrained in the rockets that have been historically available. The Titan and Delta series
of rockets are very limited in the physical space available to pack solar panels in the rocket's fairings. It might not be possible to place the
maximum mass possible in the rocket due to the solar panels' physical dimensions. Again, both Bezos and Musk are working on the problem with their
New Glenn and Starship rockets.
On top of that, placing the SPS in the ideal constantly lit orbit would reduce the useable payload by nontrivial amounts, even down by as much as
half. It could be as little as half or less of the payload to LEO would be actually placed in the ideal orbit for the SPS. That would impact the
cost in a huge way.
Additionally, there are many technologies needed to make a SPS operational that simply don't exist. The SPS were planned to use massive microwave
beams to send the power to the ground. The massive antenna needed haven't been built. Microwave transmitters in the 100's of megawatts or even
gigawatts don't exist. Space based solar cells that do not degrade far faster than their terrestrial counterparts don't exist (space is harsh
mistress). etc, etc.
All of these, but especially the economics of it all, have doomed the space-based solar power systems: the total costs of construction and
transmission of power from space cannot compete with ground based solar power. However, there are aspects than merely economics encouraging the
adoption of SPS. The primary driver actually could be national security, military or even environmental reasons.
Environmentally, cleaning up /any/ sort of electronics at the end of their life is a disaster. There are all sorts of nasty things leaking from
landfills full of dead electronics. Solar panels are no exception to this. If the solar panels are launched into space and never return because they
are disposed of on the moon or whatever. No pollution on Earth and the moon is dead, so unless you plan on terraforming the moon any time in the
future (ill advised for many other reasons), it seems like a safe bet.
However, the real driver and on topic for this board would be the development of power independent of any source on Earth is for military and national
security reasons. Imagine the ability to power the US with no oil, no combustion, no need top be worried about pollution at all. No worrying what
the Middle East is doing and its impact on the oil market at all.
Imagine an army sent over seas and their is no fuel needed, no diesel or gasoline at all. The power needed to charge the batteries in the tanks and
aircraft would be beamed from the satellites far, far above. Far out of range of almost all antisatellite weapons. The US Army proposed this in
their future warfare studies back in the late 1990s. However, costs have been historically against them and in a time frame when even basic
maintenance of aircraft was postponed and the military was first downsized and then thrown into wars where solar power was hardly a necessity, it the
concept was a nonstarter. At least until now.
Northrop signed an agreement with the Air Force Research lab to begin developing, in an incremental fashion, the technologies needed for SPS. The
antenna technology, the transmitters, light weight solar cells with long durability, etc. These are all planned for the program. The program will
culminate with the testing of the tech. TBH, probably on earth, but if it is promising enough after that, it could be done in space. If so,
then...things could get really interesting.