I believe it was purely for reasons of expansion. I don’t know exactly what our response should have been, but we need to at least acknowledge that Ukraine is defending their sovereignty and Putin/Russia are the aggressors. We should support them at least minimally.
I do agree with you. I don’t like the fact that we are the ones with all of the weapons and military might, but this does seem like a good exception. If we have these weapons and want to play the worlds policeman this seems like a place to use those weapons.