You can't invade mainland America. Way too many guns. Much easier to finance the leftist traitors destroying us from within.
The "problem" with a weakened American military is the fact that the US dollar's role as the global reserve currency is 100% dependant on America's projection of force. Weaken that force and many countries will consider other options, which could collapse our debt-strapped currency overnight. Bribing all of these countries with foreign aid doesn't work if our dollars are worthless.
This is the end-goal of China and Russia. Hard to fault them when America has routinely engaged in economic warfare against these countries, not to mention traditional warfare in so many nearby proxy nations.
You can't invade mainland America. Way too many guns. Much easier to finance the leftist traitors destroying us from within.