Is Hillary Clinton feeling a little sensitive about her position on Iran?

When Barack Obama and John Edwards hit the Democratic front-runner hard for her vote last month in favor of the Kyl-Lieberman amendment, her campaign responded by sending a mass mailing to Iowa Democrats in which she explained why she voted the way she did.

When Secretary of State Condoleezza Rice announced Thursday that the Bush administration is imposing new sanctions on Iran, the Clinton campaign distributed a statement to reporters in which Clinton said that the sanctions would “strengthen America’s diplomatic hand” but should be coupled with “robust diplomacy to achieve our objective of ending Iran’s nuclear weapons program, while also averting military action.”

And not long after that, the Clinton campaign distributed another message to “interested parties” — this one, an opposition-research memo accusing Obama of flip-flopping on Iraq. “Stagnant in the polls and struggling to revive his once-buoyant campaign,” the memo says, “Sen. Obama has abandoned the politics of hope and embarked on a journey in search of a campaign issue to use against Sen. Clinton.”

In a speech given to the Chicago Council on Global Affairs in November 2006, Obama said he could envision some scenarios in which the United States might have an “extended” military presence in Iraq. He said that “such a reduced but active presence” would, among other things, “send a clear message to hostile countries like Iran and Syria that we intend to remain a key player in this region.” “Make no mistake,” he said. “If the Iranians and Syrians think they can use Iraq as another Afghanistan or a staging area from which to attack Israel or other countries, they are badly mistaken. It is in our national interest to prevent this from happening.”

The Clinton memo argues, not unreasonably, that that’s not all that different from what the Kyl-Lieberman amendment said. While the original version of Kyl-Lieberman was substantially more bellicose, the version approved by the Senate said, among other things, that “the manner in which the United States transitions and structures its military presence in Iraq will have critical, long-term consequences for the future of the Persian Gulf and the Middle East, in particular with regard to the Government of the Islamic Republic of Iran to pose a threat to the security of the region, the prospects for democracy for the people of the region, and the health of the global economy.”

In a memo of its own, the Obama campaign focused Thursday on other language in Kyl-Lieberman — the part of the amendment in which the Senate said it’s a “critical national interest of the United States” to prevent Iran from turning “Shia militia extremists in Iraq into a Hezbollah-like force that could serve its interests in Iraq.” The Obama campaign says that’s “an entirely new rationale for keeping U.S. troops in Iraq,” one George W. Bush “can cite” as authorization to “maintain and use U.S. troops in Iraq for the purpose of curtailing Iran’s influence in Iraq and, if need be, to expand our troops’ activities beyond Iraq’s borders to pursue and attack Iranian forces.”

Translation: Clinton learned nothing from the way Bush used the military authority she and other senators gave him in 2002.

The Clinton memo goes on to fault Obama for missing the vote on the Kyl-Lieberman amendment and for failing to speak out against it until after it had passed. Obama was campaigning in New Hampshire at the time of the vote; his supporters point to the fact that Senate Majority Leader Harry Reid said the night before the vote that there wouldn’t be a vote on the amendment “anytime in the near future.”

The Clinton memo says: “That’s not the kind of strength and leadership Americans are looking for in their next president.”

Katharine Seelye argues in the New York Times’ Caucus blog that the Clinton memo represents “some of the strongest language” the campaign has used “in public” against Obama yet. That’s true, but only to a degree: While Clinton herself has mostly tried to appear above the fray — her “naive and frankly irresponsible” attack on Obama notwithstanding — her campaign frequently encourages reporters to go after Obama. Sometimes, the push is off the record. Sometimes, it’s not. Two weeks ago, Clinton campaign spokesman Phil Singer put out a statement faulting Obama’s Iran-based criticism of Clinton as “the same old attack politics” launched by the “flagging campaign” of a candidate whose “poll numbers” were “falling.”

Does the Clinton campaign see vulnerability on Iran? Is its counterattack just another effort to cut off any possible avenue for her challengers to gain the ground they haven’t been able to cover so far? Or is the Clinton campaign just trying to telegraph to Democratic voters that it’s willing to play hardball — in a way, say, that the John Kerry campaign sometimes didn’t — if Clinton gets the nomination and the GOP attacks that come with it?

That’s hard to say. What’s not hard to see is the message that Team Obama wants voters to hear now: Clinton gave Bush the green light for the Iraq war in 2002, and now she’s giving him something that feels like — or at least can be made to look like — one on Iran now.

“All of the political explanations and contortions in the world aren’t going to change the fact that, once again, Sen. Clinton supported giving President Bush both the benefit of the doubt and a blank check on a critical foreign policy issue,” Obama spokesman Bill Burton said Thursday. “Barack Obama just has a fundamentally different view.”