> I think they're seeing that against the alternative: a global war. Which is definitely one of the other options on the table right now.

Except that's not an either-or alternative. Even if the US had a civil war and somehow disappeared, other belligerent actors would be free to start conflicts that had been held back by US pressure. You still have your "global" war. Like if the US disintegrates right now, Europe can kiss all of Ukraine goodbye, and probably the Baltics, too.

And even if somehow the US was the only problem (it's not), there's a decent chance that the end result of a civil war is a non-fragmented and even more belligerent US.