Agreed.
Which is why I've never understood both of these propositions are not clearly in America's best interests:
1. Iran is run by a theocratic regime committed to the destruction of Israel and the establishment of of new caliphate, such that allowing it to acquire a nuclear weapon is a threat to the region and, in turn, to the United States and global security.
2. Russia is run by a dictator who has openly and repeatedly stated his desire to reconstitute - by any means necessary - the former Russian/Soviet Empire, such that contesting Russian aggression, particularly in Europe, is a threat to NATO, to the United States, and to global security.
I see no reasonable argument to the contrary, nor do I see any way to find (1) is true while denying that (2) is true.