If the leaders of the Iranian regime were worried about Jeffrey Goldberg’s prediction that Barack Obama would confound the world and launch a U.S. military strike designed to save Israel from nuclear destruction, they can now calm down. Secretary of Defense Leon Panetta made it crystal clear at a Pentagon news conference yesterday he has no intention of supporting an American attack on Iran’s nuclear facilities. Echoing remarks uttered by his predecessor Robert Gates, Panetta said a U.S. strike would only deal a temporary setback to the Iranians and emphasized his fear that the “unintended consequences” of an American offensive would negatively impact the position of U.S. forces elsewhere in the region.

Panetta’s fears about conflict with Iran are reasonable. We don’t know whether it will be possible to completely eradicate their nuclear facilities (though a U.S. campaign would have a much greater chance of success than one conducted solely by Israel) and war with Iran could set off a series of other struggles around the region which would, at best, be messy, and at worst, be disastrous. But by publicly throwing cold water on the idea the United States is ready and able to militarily squash Iran’s nuclear ambitions, Panetta has sent a dangerous signal to Tehran that the Pentagon intends to veto any use of force against them. Combined with Russia’s pledge to block any further sanctions on Iran, the statement should leave the Khameini/Ahmadinejad regime feeling entirely secure as they push ahead to the moment when they can announce their first successful nuclear test.

For several years, leading voices in the Pentagon have sought to dampen any interest in attacking Iran. Part of it can be put down to the natural reluctance of military leaders to actually use the forces at their disposal. Part can also be attributed to a very understandable worry about launching a new war while the old ones in Iraq and Afghanistan were still raging. But it also reflects a sense by many in Washington that a nuclear Iran can be contained without too much bother. Israel’s fears of an existential threat to its existence and the equally profound worries of Arab countries about the prospect of a nuclear-fueled Iranian hegemony over the region just don’t resonate with those who, like many in Europe, fear a fight to stop the ayatollahs from getting the bomb more than they fear Iranian nukes.

But whatever the motivation, what Panetta has done with his statement is to alert the Iranians to the fact that the United States has no intention of doing anything but talk about stopping the Islamist nuclear threat. This comes as no surprise to Iran, because its leaders have long since pegged President Obama as a weakling whom they needn’t worry about. A year of the administration’s comic attempts at “engagement” followed by two more of unsuccessful attempts to forge an international coalition in favor of tough sanctions aimed at Iran have taught the ayatollahs to discount any possibility that Obama will take action against them.

It was bad enough the Iranians already believed this to be true, but by speaking out publicly in this manner in an effort to stop any speculation about Washington still considering the possibility of the use of force, Panetta has given them a guarantee they have nothing to fear from the United States.

Panetta is also sending a message to Israel. Going back to the George W. Bush administration, the U.S. has refused to give the Israelis a green light to take out Iran’s nuclear facilities. By speaking of “unintended consequences,” there’s little doubt Panetta is seeking to repeat that signal. While Jerusalem may still hold onto some hope that the U.S. will eventually change its mind when presented with an imminent Iranian threat, the Netanyahu government must be forgiven for believing they are now clearly on their own.