Having an unassailable conventional military isn't a waste of money because terrorists are the US's primary threat--terrorists are the US's primary threat because the US has an unassailable conventional military.
I'll take the Taliban over the Soviets or Axis as a primary threat, easily. The couple of generations before mine worried about the bomb, and the generation before that worried about the Japanese landing in San Francisco. All we have to worry about is having airplanes hijacked? That's success, not failure.
Well, to be fair, our enemy was the Soviet Union when these projects were started, and stealth technology would have been very helpful in a war against them.
It's interesting how the world has changed. Any political entity with the ability to make war has realized that wars do not help them get richer, and so everyone pretty much gets along. It's the people with nothing to lose that want to start wars now.
I'll take the Taliban over the Soviets or Axis as a primary threat, easily. The couple of generations before mine worried about the bomb, and the generation before that worried about the Japanese landing in San Francisco. All we have to worry about is having airplanes hijacked? That's success, not failure.