Cheering on Ukrainians killing Russians isn't "cheer-leading for a tragic war". It's cheering for victory over evil.
As for "having no part in it", I'm literally in Kyiv right now, for good reasons. Among them being there's a big Bitcoin community in Ukraine and this trip I did two panels at Bitcoin events.
You're ultimately just trying to make excuses to let evil go unpunished. Evil that if not stopped in Ukraine, will certainly continue to spread. Russia has been invading neighbors for centuries. As a Canadian I'm well aware of the fact that Russia and Canada share a long northern border, and Russia has been challenging Canadian sovereignty in the north.