The US isn't facing a two-front war, exactly – but as the Pentagon begins its new push in Iraq, the Bush administration simultaneously is increasing military and political pressure on Iran.
The point is to counter Iranian meddling in Iraq, while making the nation's ruling mullahs think harder about any plans to intensify their nuclear program, according to White House officials. They say further US moves are likely in the weeks ahead.
But it's not clear that such escalation will accomplish more than it will cost, say some experts. Any actual attack on its agents or interests might cause Iran to redouble its current support for Iraqi Shiite militias. Or Tehran could decide to outflank US forces by causing trouble elsewhere.
Iran "has the ability to act throughout the region and beyond given its ties to groups such as Hizbollah and Hamas," said Richard Haas in remarks prepared for delivery before the Senate Foreign Relations Committee last week.
The latest move in the developing US-Iran chess match came on Saturday, when President Bush defended US action against Iranian agents inside Iraq as a crucial defense for American troops. US forces have been authorized to kill or capture Iranians if they deem it necessary, under a new policy first reported last Friday in The Washington Post.
"If somebody is trying to harm our troops or stop us from achieving our goal ... we will stop them," Mr. Bush said following a meeting with top military commanders at the White House.
The US has long worried that Iranian agents inside Iraq have been providing Shiite fighters with sophisticated bomb technology that has made roadside explosions more deadly to US troops. In the recent past, some Iranians have been detained, interrogated, and then set free. This so-called "catch-and-release" policy may now be a thing of the past.
"If you're in Iraq and are trying to kill our troops, you should consider yourself a target," said Secretary of Defense Robert Gates last week in response to a reporter's question about Iran.
Meanwhile, the US has dispatched a second aircraft-carrier battle group to the Persian Gulf as an apparent symbol of its intention to carry out airstrikes against Iranian targets, if necessary. And it has increased pressure on foreign banks and financial institutions to cut ties to Iranian counterparts – warning them that they risk losing access to US financial markets unless they stop doing business with Tehran.
Of course, the US goal isn't just to stop Iranian aid to Shiite militias. Iran's nuclear program has been continuing apace. On Saturday, a key Iranian lawmaker, Alaeddin Boroujerdi, said Iran was currently installing an array of 3,000 centrifuges at a uranium-enrichment plant.
If true, such a move would represent a slap in the face to the international effort to curtail Iran's disputed program. Three thousand centrifuges would be more than enough to produce fuel for a nuclear bomb.
However, an official of Iran's nuclear agency said over the weekend that "no new centrifuges have been installed in Natanz," referring to Iran's main nuclear facility. At the time of writing, this discrepancy in statements had not yet been resolved.
It's possible that Iran itself is split over whether to take a path of confrontation or accommodation with the US and the international community at large.
Recently a majority of Iran's parliament sent President Mahmoud Ahmadinejad a letter criticizing him for his high-profile foreign travel and blaming him for the country's economic troubles.
That's an indication that international diplomatic pressure and financial sanctions are working, according to some US experts.
Iran hasn't always worked at cross-purposes with the US in its struggle against extremist Islamist terrorism. The Iranian government gave $300 million in aid to the government of Afghanistan, and furnished the US with intelligence about the Taliban.
"They were helpful in Iraq, according to Secretary Gates, until early 2004," noted Lawrence Korb, a senior fellow for the Center for American Progress, in congressional testimony last week.
In some ways, their strategic goals for the region match those of the US. It is unlikely that the Shiite mullahs of Iran would like to see Al Qaeda win a haven in the Sunni-dominated outlying regions of Iraq, for instance. Nor would Tehran likely want any further collapse of order in Iraq, leading to a failed state and a refugee crisis on Iran's border.
Still, it's clear that Iran has recently been troublesome. It appears eager to make the US experience in Iraq as difficult as possible.
But for the US, the problem with squeezing Iran while it struggles with sectarian violence in Iraq is that it is trying to stabilize one country while destabilizing its neighbor.
"We have to choose what our goals for the region are, and right now, unfortunately, the president's plan has us going in two different directions at once," said Robert Malley, director of the Middle East and North Africa program for the International Crisis Group, in testimony to the Senate Foreign Relations panel.