Smaller countries that don’t have geopolitical significance may be able to transition to socialism undisturbed. But if they get the ball rolling, it could start inspiring other countries to do the same and start wars.

But if you’re talking about word war as in China vs. US and allies in a war against ideology like the US and USSR, then no. China might push ideology if they find themselves in the position of hegemony, but in an active conflict they will not care whether or not their allies are communist.