Win McNamee / Getty Images President Obama during a press conference in the East Room of the White House, Aug. 9, 2013 in Washington, DC.

When he first ran for President, Barack Obama cast himself as the man to support if you thought the Iraq war was a stupid mistake. “We must not repeat the mistakes of Iraq,” he said in August 2007, lamenting what he called a war of “undetermined length, at undetermined cost, with undetermined consequences.”

But in a stinging irony, Obama now finds his plans for a military strike on Syria hamstrung by memories of George W. Bush’s war. And many of the same objections that Obama once voiced are being hurled back at him by opponents of an intervention in Syria.

“All of this [talk of striking Syria] makes one recall the events that happened 10 years ago, when, using false information about Iraqis having weapons of mass destruction, the U.S. bypassed the United Nations and started a scheme whose consequences are well known to everyone,” Russia’s Foreign Ministry said in a statement this week.

The Obama Administration is pushing back hard against such talk. “Iraq and Syria are in no way analogous,” State Department spokeswoman Marie Harf told reporters Thursday. The question of whether to respond to the Assad regime’s suspected use of chemical weapons “is categorically different than the conversation we were having about possible action in Iraq, period.” Harf said.

It’s not clear whether that argument will stick in a country with dark memories of a decadelong conflict, featuring terrorism, torture and beheadings, which cost more than 4,500 American lives and, by some estimates, more than $2 trillion dollars.

But the Iraq effect is something larger. It has dramatically raised skepticism about the U.S. government’s rationale for applying military force in the name of American security. Both Congress and the news media, two institutions burned badly by the Iraq debacle, are asking particularly pointed questions about Obama’s plans. The benefit of the doubt that Commanders in Chief once enjoyed has crumbled.

The objections come in three main forms. The first is the reliability of U.S. intelligence about weapons of mass destruction. “[W]here is the proof that President Bashar al-Assad of Syria carried out the attack?” a New York Times editorial asked on Thursday. “Given America’s gross failure in Iraq — when the Bush Administration went to war over nonexistent nuclear weapons — the standard of proof is now unquestionably higher.” (The Times, of course, has reason to be especially sensitive to this question.) Pressed on CNN on Thursday about whether he had “hard evidence” of a regime-ordered chemical attack, House Intelligence Committee chairman Mike Rogers hedged. “Well, that’s hard to say … We don’t have the crib notes of Assad writing to his commanders [saying], ‘Hey, let’s use chemical weapons.’ No, we don’t have that.” Rogers added that intelligence convinces him that “the Assad regime was responsible” for multiple chemical attacks.

(MORE: How U.S. Strikes in Syria Could Make Things Worse)

Second is fear of an escalating commitment and other unexpected outcomes. Iraq-war supporters who’d been led to expect a quick handoff to a new government in Baghdad were horrified as American involvement deepened there; the Bush Administration failed to plan adequately for a breakdown in Iraqi society. Those bad memories were evident in the letter House Speaker John Boehner sent to Obama this week, demanding answers about what steps would follow an initial round of air strikes and how Obama would pay for his mission. “It’s critically important that we remember about unintended consequences,” Democratic Senator Elizabeth Warren said Wednesday.

Third is an enduring suspicion that the U.S. wants to overthrow Middle Eastern regimes and impose democracy. Assad was likely trying to exploit this sentiment in a recent interview with the Russian newspaper Izvestia, in which he said the West is “seeking to install ‘puppet’ leaders” in the Middle East. “Our message to the world is straightforward: Syria will never become a Western ‘puppet’ state,” Assad said. The Obama Administration has sought to make clear that toppling Assad is not its goal: “The options that we are considering are not about regime change,” White House press secretary Jay Carney said earlier this week. (Although there’s little sign that Obama wants to topple Assad, he has called for the Syrian ruler to leave power.)

For Obama and his aides, the comparisons to Bush must be somewhat surreal. “I think we’ve been clear in this Administration that we are not going to repeat the same mistakes of the Iraq war,” Harf insisted on Thursday. But it’s not clear that the world is listening.

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