Let's assume for this discussion that some few NHI craft have been recovered and studied to the point where some technology can re gleaned if not reverse engineered. We also assume that humans have been working to get technology from these craft for decades.
People can be smart when correctly applied and organized so it's possible that Alien Reproduction Vehicles have been designed and created for decades by humans, and that many or most UAP sightings are of the ARVs and not from NHI.
We've heard allegations that the actual NHI craft have an unknown power source, that they can perform thousands of Gs, stay up in the air for prolonged times, and move without a thermal signature.
Imagine that we had solid proof that this would work a long time ago, we might have spent a lot of time perfecting it in secret so that companies or countries might have this technology and we are just beginning to see the first use of it prior to potential large scale war.
new technologies often emerge in war time, things like planes, metal hulled ships, tanks, even the popularity of bananas in the US, and much more have arisen during war time, and this may be like 1914 with airplanes for what we are going to see in out future with the proliferation of technology such as this.
Now here are some of the potential things we can do with this technology, if we had it according to a 2009 DIRD:
"If an ultra-high-intensity HFGW flux impinges on a nucleus 1 it is possible that it could initiate nuclear fusion at a remote location"
"HFGWs could theoretically be used for propulsion and control of the motion of objects... and remote control of clouds of .. vapors. Gravitational field changes by one or more HFGW generators could urge a spacecraft in a given direction, causing a lower static gravitational field in front of a vehicle (it "falls" forward) and a higher one behind (providing a "push"). The concept is that the mass essentially "rolls" down a "hill"... 1975,"
"A novel means of imaging or HFGW surveillance ... for observing activities and materials in three dimensions, within and below structures and within the Earth and its oceans. Gravitational waves, including HFGWs, pass through most material with little or no attenuation; but although they are not absorbed, their polarization .. phase velocity .. refraction or bending of gravitational rays), backscatter, and/or other characteristics can be modified by a material object's texture and internal structure"
", but one can certainly speculate that the human need for connectedness and communication knows no bounds. " they mean this about like phones but I want to leave it last for what communicate can give us.
I wonder how they plan to overcome the problems the last attempts had, frequent fouling of a firing rails. large electrical battery systems would make the power potentially possible. I wonder if this is related to that DIRD about ways to get power in hostile areas with no domestic power sources.?.
If this is successful then I think we'll see railgun weapons like rifles, though I'm not sure we'll still be using as many human fighters at that point.