I appreciated the way you analysed the issue, yet as for...

...The US is pretty much invincible, at least in a conventional war, unless you're willing to live off berries in a cave for a decade. Some reserves are necessary.

On one hand, invincibility of an army is not eternal and, thus, no one can pretend detain this as a property, for ever; it can often be challenged and I can cite as example of a recent past when the Emperor Napoleon, Hitler and Hirohito did enjoy the defeat their "invincible" armies. And on the other hand, don’t you think that this could be one case among others that might accelerate the fall of the American empire?

Or maybe things are not as dark as that.

Just a premonition of a foreigner, really curious.