A friend of mine works on F16's. He says they don't really have half the plans to re-create or fix them and another third are just outright wrong, but instead they have to reverse engineer them. I exaggerate a bit. Still it's enough so even if another country stole all the plans they'd not be able to build their own F16s without spending massive amounts to re-engineer half of it and avoid the known issues.

That's long been America's main advantage. We can apparently spend insane amounts of money on this stuff, which would bankrupt other nations.

It's an odd but seemingly effective strategy. I'm not sure if it's planned or really just a happenstance of Washington politics. Also explains the F35 being absurdly expensive, maybe its a "feature" not a bug.