[akhmatova]

There are two ways for a war to end: One way is for one side or the other to be basically destroyed. The other way is some negotiated settlement

History readily provides an infinite number of counterexamples, more or less along the theme of "mutual, or one-sided exhaustion (but still far short of one-sided destruction)". WW I, the US/Soviet failures in Afghanistan and most colonial occupations for that matter immediately spring to mind.

[blub]

Mutual or one-sided exhaustion is indistinguishable from regular war until it happens and at least in this case the hope of reaching such a state is based on continuous escalation.

Negotiated settlement is very broad and would include such “exhaustion” cases. Should it be treated separately? For a theoretical discussion on how to end war, perhaps. But in this particular case, the US is playing a dangerous escalatory game and it neither can it be guaranteed that it will achieve the stated purpose, nor that this is indeed the actual purpose. Perhaps the actual goal is regime change, or taking back Crimea or another thing which has totally different implication from exhausting an opponent.