Defense Secretary Leon Panetta spoke at the American Israel Public Affairs Committee this morning and delivered the same message heard earlier this week: There's no greater regional threat than a nuclear armed Iran, there is no policy of containment, and the U.S. is "determined to prevent Iran from obtaining a nuclear weapon."

Panetta was the first defense secretary to speak before the group in 20 years, and his speech outlined his close relationship with Israeli leaders and the U.S. commitment to its ally.

His comments on Iran came at the very end of the speech and reaffirmed the tough comments we've heard about Iran in the past few days.  "No greater threat exists to the security of Israel and to the entire region - and indeed the United States - than a nuclear armed Iran.  As President Obama made clear here on Sunday and as he has said consistently, the United States is determined to prevent Iran from obtaining a nuclear weapon.  Let me be clear - we do not have a policy of containment; we have a policy of preventing Iran from acquiring nuclear weapons."

Panetta noted  the Obama administration's pressure on Iran, which has led to "crippling sanctions and growing isolation."  He said Iran faced a choice: "Ether meet their international obligations and rejoin the community of nations, or violate their international obligations and face severe and growing consequences."

The U.S. has made clear that it wants diplomacy to work, but "we will keep all options - including military action - on the table to prevent Iran from obtaining a nuclear weapon. " He described that as "a last alternative when all else fails, but make no mistake, we will act if we have to."

Panetta said that as  the president has made clear, the U.S. does not bluff. "  He listed the surge of troops into Afghanistan, the Libyan bombing campaign, sending Navy ships through the Strait of Hormuz despite Iranian threats and the bin Laden raid as examples of how President Obama "has shown that we will do whatever is necessary to protect our people, our allies and our interests."

The defense secretary closed by stressing that  strong U.S.-Israeli cooperation is essential when it comes to dealing with Iran.   "I believe - I truly do - that we will succeed if the United States and Israel continue to work so closely together, and forge an international consensus to compel Tehran to change course.  That is my pledge, and that is the solemn and sacred pledge of the United States.  We are stronger when we act as one.  We are stronger when we work together to support a sovereign and secure Israel.  We are stronger when we both embrace our histories that pledge us to fight for what is right and for the dream of giving our children a better and more secure life.