>>510136586 (OP)By hurting Russia, duh.
>>510137255A lot of ways, the most obvious example would be preventing a greenlight being given to invade Taiwan. It would be geopolitically catastrophic for the US to abandon its prior commitments such as arming Ukraine because then all of the US's allies realize the US isn't interested in maintaining its hegemony anymore so they look elsewhere. This leads to things like arms races around the world, including nuclear arms races (which every single superpower is opposed to for obvious reasons).
That's a very brief overview of a couple of elements of it, usually people who ask silly questions know this to begin with and are trying to propagandize low IQ individuals (such as most of /pol/).
No one in Russia or China tells Putin or Xi 'we should isolate from the rest of the world, that would be China/Russia first!' because they would get laughed out of the room and immediately fired for being an idiot. It's only in the West that this demoralization propaganda gets given any serious time of day.