Almost all government R&D spending is via small(ish) grants to academia for entirely unfocused "blue sky" research. Once you accept the premise that research sh

Almost all government R&D spending is via small(ish) grants to academia for entirely unfocused "blue sky" research. Once you accept the premise that research should have no specific application in mind, it becomes impossible to determine if it's actually doing anything legitimae or is just fraud, which is why there's so much non-replicable crap coming out of universities. Military R&D is done with a specific, achievable goal in mind. It's not blue sky, it's more like "we need a better missile, how do we do that". Most of the real impactful innovations out there came as a side effect of trying to achieve some other goal, with only rare exceptions (ChatGPT?). As for why other countries don't, their military spending is too small to catch up and then exceed the state of the art. All the money gets spent on buying stuff the US developed.