And do you think the bad guys care about how the good guys self identify? Do you think bad guys care about whether the good guys limit themselves to legal, UN sanctioned operations?
What do you think will deter future bad guys from sending Panzers into Poland?
a) International Law and a lack of UN authorization
or
b) The USA
If you answered (b) then welcome to the real world.
Effectively, and this may be galling to some, we should all be thankful that the current superpower is the most fair, restrained and enlightened of all the hegemons to have graced the pages of history (and we should be damn glad that it isn't one of Russia, China, etc in its place).