Dying empires have a tendency to get embroiled in multiple disastrous conflicts as they attempt to reassert their position of power in the world.

Of course, this is just a pattern, it doesn't really mean the US is doing the same thing. And it could be a chicken and egg situation, where the costly wars are what accelerate the decline, rather than the decline causing them to start wars.

I invade you with computers made in china, designed in america, with materials from africa.