Like Israel. A good reason to be good at that.
They survived as long as they did because we lived in a general peaceful era where you had no viable near peer threat. That is, if you think about it, a good thing: Peace.
The only threats we did face were retards like in the Middle East. But they cannot counter our military technologically since they have no real R&D, industry, etc. Even a 1970s Dragon missile (ATGM- predecessor to Javelin) would work perfectly fine there. The real danger we faced was from the proliferation of advanced weapon systems i.e. from our allies, our own (that happens), Russia, China.
Today, this war in Ukraine “should” be sending a clear and even scary message to us that we are in dire need of force modernization in all aspects (structure/organization, training, equipment).