Michele Bachmann's Factual Inaccuracies

The factual smack-down takes place at about the 4:00 mark. Bachmann claims that...
Iran has also stated they would be willing to use a nuclear weapon against the United States of America. I think if there’s anything that we have learned over the course of history, it is that when a madman speaks, we should listen. And I think in the case of Iran, that is certainly true.
To which, Amanpour replies:
Congresswoman, of course the United States is concerned about the nuclear program. Iran denies that it has one, so it hasn’t threatened to use them.
The whole interview is worth watching, as Bachmann seems to squirm nearly the entire time.