TUNIS, Tunisia (AP) - Syrian President Bashar Assad's use of helicopter gunships to counter a civil uprising will prove to be "a nail in Assad's coffin," U.S. Defense Secretary Leon Panetta said Sunday at the outset of a five-day Mideast tour.
While giving no indication that the Obama administration is contemplating military intervention, Panetta said it is increasingly clear that the Syrian crisis is deepening and that Assad is hastening his own demise.
"If they continue this kind of tragic attack on their own people ... I think it ultimately will be a nail in Assad's coffin," Panetta told reporters traveling with him from Washington. "His regime is coming to an end."
Panetta said he would use his meetings in Tunisia, Egypt, Israel and Jordan to reinforce an international consensus that Assad must step down and allow a peaceful transition to a democratic form of government.
He said he also will continue consultations on efforts to ensure that Syria's stockpiles of chemical weapons do not fall into the wrong hands.
Panetta will be in Israel just days after U.S. Republican presidential hopeful Mitt Romney, who has cast the Obama administration as too soft on Iran and insufficiently supportive of the Jewish state.
In a speech in Jerusalem Sunday, Romney said the United States has "a solemn duty and a moral imperative" to block Iran from achieving nuclear weapons capability. He steered clear of overt criticism of President Barack Obama, even though he said the threat of a nuclear-armed Iran "has only become worse" in the past five years.
Panetta declined to respond. "I'm just not going to get into that game of commenting on what candidates do," he said.
Panetta said he believes Israeli leaders still support an international campaign of economic, political and diplomatic pressure on Iran to prevent it from obtaining a nuclear weapon.
"My view is that they have not made any decisions with regards to" attacking Iran, he said.
While in Israel, Panetta planned to visit an air defense battery that uses technology developed in part with U.S. support to shoot down short-range rockets. Israel has suffered thousands of rocket attacks from Hezbollah militants in Lebanon and Hamas forces in the Gaza Strip in recent years.
The air defense system, called Iron Dome, has been an important success and serves to deter attacks from Iranian proxies, Panetta said.
He called Iron Dome an example of expanded U.S.-Israeli cooperation.
"We have achieved a level of defense cooperation that is unprecedented in our history," Panetta said. "And my goal is to deepen that relationship even further."