One big difference is that Russia is the aggressor. Against Iran, the US would be the aggressor. Force may be unavoidable to stop aggression, but if you want a safer world, invading random countries for questionable reasons is a really bad idea.
One big difference is that Russia is the aggressor. Against Iran, the US would be the aggressor. Force may be unavoidable to stop aggression, but if you want a safer world, invading random countries for questionable reasons is a really bad idea.