If we were going to invade Iran, or at least surgically remove their nuclear capability, where would we attack from?
Think about it.
As for North Korea, what prevents us from attacking them is South Korea.
Libbie like 2fast4u wanted us to attack Iran with the Taliban in charge of Afghanistan, Saddam in charge of Iraq and the ISI in charge of Pakistan. But it's a moot point anyway. The liberals support a nuclear armed NK and Iran since they always cheer for the bad guys.