U.S. keeps talking tough with Iran

Tensions between the U.S. and Iran continue to escalate.

The White House is warning Tehran not to shut down the Strait of Hormuz, an action that would disrupt the flow of oil from the Persian Gulf.

But the rogue nation isn't showing any signs of listening.

National security correspondent David Martin reports that, by some estimates, closing the vital passageway could double the price of oil. And Defense Secretary Leon Panetta says the U.S. wouldn't let such a move stand.

Most officials do not believe Iran would take such drastic action, Martin says, since it would cripple its own oil exports and alienate every country that depends on Middle East oil.

Still, the Iranians made the threat in the midst of naval exercises showing off weapons it would use to close the strait.

To see Martin's report, and get some perspective on the escalating tensions by viewing a Jeff Glor interview of Brig. Gen. Mark Kimmitt, who was an assistant secretary of state for political-military affairs under President George W. Bush and served as deputy assistant secretary of defense for the Middle East, click on the video above.