(2004) U.S. Senate candidate Barack Obama suggested that the United States one day might have to launch surgical missile strikes into Iran and Pakistan to keep extremists from getting control of nuclear bombs.
http://www.chicagotribune.com/news/printedition/chi-0409250111sep25,1,4555304.story?ctrack=1&cset=true Here I think Obama is wrong. Iranian nuclear sites appear so well hardened that the only missiles capable of destroying them would be...nukes. To launch nuclear missiles at a country merely because they might be building weapons of their own seems morally unjustifiable, and strategically unwise.
In order to guarantee the destruction of such sites, we'd have to launch multiple, big missiles. Fallout all over Iran. Thousands of civilian deaths from cancer, both in Iran and unlucky downwind countries. And even then, can we be sure we stopped them? How good was our intel on weapons of mass destruction in Iraq? Can we trust hypothetical information on Iranian weapons programs to be any more reliable, or immune from political tampering? doubtful.
If we can't stop the Iranians by sanctions and similar means, or some sort of highly speculative covert action, I think we're going to have to live with them; as we lived with the Soviet Union during the Cold War, by a strategy of mutually assured destruction. I think Ahmedinejad and his cronies are sane enough to know that any attack on the US, Britain, Israel, etc. even by terrorist proxies would result in massive retaliation that would wipe out Iran. It won't be a friendly peace, but it probably beats a nuclear war.