War with Iran is the last thing Barack Obama needs with the American economy in dire trouble and a tough White House election campaign looming next year, according to officials in Washington as well as political analysts.
But while the Obama administration is desperate to avoid another conflict - it would be America's fourth in a decade - the drumbeat from Israel has been growing louder.
The Israeli cabinet was reported on Wednesday to be debating whether to launch air strikes on Iranian nuclear sites in the coming weeks. The Prime Minister, Benjamin Netanyahu, and the defence minister, Ehud Barak, are lobbying in favour of action, but other senior ministers are urging caution.
In response, Iran has warned, as it has in the past, that any attack by Israel would result in retaliation against the US. The Iranian news agency ISNA quoted Hassan Firouzabadi, Iran's military chief, as saying: "The Zionist regime's military attack against Iran will inflict heavy damages to the US as well as the Zionist regime."
The rhetoric from Tel Aviv and Tehran is making some within the Obama administration nervous.
A Washington official familiar with the issue acknowledged the temperature has been rising and that Israel introduced an unpredictable element.
He reiterated, however, that the policy of the Obama administration was to pursue all diplomatic channels, backed by tougher sanctions, and avoid military action.
A congressional hearing on Iran last week was told that the Pentagon has a series of contingency plans for military action, ranging from all-out war to limited operations. Obama had signed off on these, the hearing was told.