Afghanistan is known as the "graveyard of empires" for a reason. The US spent 20 years and IIRC $7 trillion on our mid-east frontiers in Iraq and Afghanistan.

We are currently illegally occupying 1/3 of Syria, and planning a new military base on the land we are illegally occupying there.

And for what? Did we get western-style democracies anywhere there? No, the Taliban took over (again!) in Afghanistan immediately after we left. Iraq is no friendlier to the US than it was when we were supporting Saddam Hussein in the 1980s. The Arab League has just re-admitted Syria as a member. We spent a fortune AND lost face in all those frontier conflicts.

Now we repeating that mistake in Ukraine, and look to repeat it once more in Taiwan.

Definitely not sexy, but our slow bleed in these useless frontier wars is a definite factor in the domestic decline of the US over the last 60 years (including Vietnam).