To henkster’s excellent essay I would just emphasize we seem to have two irredentist powers who are willing to use military force to achieve their aims until someone is willing to try to stop them, Russia and China. The mood in the presently fragmented Arab world is overwhelmingly irredentist over reclaiming the land of Israel. The current administration is not remotely inclined to stop any of them. Given the public mood and the destruction wrought on our economy and military, I’m not sure that a future competent administration would be able to do so.
Russia is a state-actor kleptocracy and demographics are killing it. Same thing with China. Who on the world stage or even in the wings is in a position to take America’s place in the world?