In foreign policy as in much else, President Barack Obama has relied on words rather than actions. So it is difficult to take seriously his threat, expressed in an interview Friday with ABC News that aired Sunday on This Week, to launch military action against Iran to prevent it from becoming a nuclear power. Indeed, the Iranian regime welcomed Obama’s retreat on a strike against Syria as a step in the right direction.

“We are hopeful that American politicians have some rationality so they avoid extremist behavior, and the events of the last few days and the decisions that have been taken indicate this rationality,” said the speaker of the Iranian parliament, Ali Larijani, according to the Jerusalem Post and Iran’s ISNA on Sunday. In addition, Obama is known to be reaching out to Iranian president Hassan Rouhani to renew nuclear talks.

That diplomatic effort comes after years of stalling, in which the Iranian regime has used talks to play for time, installing new nuclear centrifuges to accelerate uranium enrichment in violation of UN Security Council resolutions, replacing equipment damaged by the Stuxnet virus (for which the Obama administration proudly took credit, a matter of dispute among Israeli officials who say the idea was theirs).

In Friday’s interview with ABC News, Obama said: “I think what the Iranians understand is that the nuclear issue is a far larger issue for us than the chemical weapons issue, that the threat…against Israel that a nuclear Iran poses is much closer to our core interests. My suspicion is that the Iranians recognize they shouldn’t draw a lesson that we haven’t struck [Syria] to think we won’t strike Iran.” 

Reports indicate, however, that the Obama administration has already turned down at least one proposal by Israel to strike Iran’s nuclear facilities. The Syria crisis not only sent a signal of American weakness and vacillation, but also likely expanded Russia’s influence in the region. Russia is the chief source of nuclear components for Iran, and is known to oppose any military strike by the U.S. against the Iranian regime.

While Americans broadly support a pre-emptive strike in Iran–in contrast to overwhelming opposition to a strike against Syria–it is unclear whether they would trust Obama to lead a successful Iran strike in the wake of the Syria debacle. A recent Gallup poll shows that the Syria crisis has yet to affect perceptions of Obama’s job performance on foreign affairs, which hovers at 42%, near where it has been for months.