The 10th anniversary of the invasion of Iraq has prompted plenty of analysis of the mistakes made there, along with a few tendentious claims that “the same people” who supported war in Iraq are now pressing for U.S. intervention in Syria. I’m one of those people. So, to paraphrase the polemicists: Did I learn nothing from the last decade? Do I want to repeat the Iraq “fiasco”?

Let’s start with the second question. Iraq was unquestionably costly and painful to the United States — in dollars, in political comity and, above all, in lives, both of Iraqis and Americans. It hasn’t turned out, so far, as we war supporters hoped. Yet in the absence of U.S. intervention, Syria is looking like it could produce a much worse humanitarian disaster and a far more serious strategic reverse for the United States.

Iraq and Syria are similar in many respects. Both are unnatural creations, drawn on a map by British and French diplomats in 1916. Both contain a potentially volatile mix of ethnic groups and sects, including Shiites, Sunnis, Kurds and Christians. Both were held together through the 20th century by merciless dictators who, representing a minority sect, used repression, militarism, Arab nationalism and, when necessary, genocide to hold their states together. Both Saddam Hussein and the Assad regime in Syria courted terrorists and stockpiled weapons of mass destruction — but the Assads, unlike Saddam, never had to give up their chemical and biological arsenal.

It was inevitable that, with the exhaustion of their ideologies and economic models, these states would unravel — and that Iraq’s repressed Shiite majority, like Syria’s downtrodden Sunni majority, would demand redress. The difference is that the U.S. military triggered the transformation of Iraq, quickly disposing of the old regime and buffering the subsequent sectarian struggle. In Syria it has leaned back, providing humanitarian aid and prodding the opposition to unify but otherwise refusing to intervene.

The results? No U.S. soldiers have been killed or wounded in Syria, and the cost is in the hundreds of millions rather than the hundreds of billions. But so far, the larger humanitarian price of Syria has been far greater. With 70,000 killed in just two years, Syria is producing fatalities at twice the rate of Iraq after the U.S. invasion; with 1.1 million people having fled to neighboring countries and 3 million expected by the end of this year. Syria is on course to produce 50 percent more refugees than Iraq after 2003.

In Iraq, the United States faced down al-Qaeda and eventually dealt it a decisive defeat. In Syria, the al-Qaeda affiliate Jabhat al-Nusra is steadily gaining strength — and prompting, across the border, a revival of al-Qaeda in Iraq. The Obama administration’s hands-off approach offers no means for checking this menace or for preventing al-Qaeda from eventually gaining control over chemical and biological weapons.

The Iraq war prompted low-level meddling by Iran, Syria and other neighbors but otherwise left the surrounding region unscathed, thanks to the U.S. presence. Syria’s unchecked carnage is spilling over into Lebanon and Iraq, and it threatens U.S. allies Israel, Turkey and Jordan. Iran, Persian Gulf states and other neighbors are pouring in weapons and, in some cases, fighting units.

Iraq prompted a temporary souring of relations between the United States and France and Germany, and Arab Sunni monarchies never fully accepted the Shiite-led government that democracy produced. But U.S. influence in the Middle East remained strong. Now it is plummeting: Not just Britain and France but every neighbor of Syria has been shocked and awed by the failure of U.S. leadership. If it continues, Syria — not Iraq — will prove to be the turning point when America ceases to be regarded as what Bill Clinton called the “indispensable nation.”

Does all this mean that the United States should be dispatching hundreds of thousands of troops to Syria? Of course not. The tragedy of the post-Iraq logic embraced by President Obama is that it has ruled out not just George W. Bush-style invasions but also the more modest intervention used by the Clinton administration to prevent humanitarian catastrophes and protect U.S. interests in the 1990s. As in the Balkans — or Libya — the limited use of U.S. airpower and collaboration with forces on the ground could have quickly put an end to the Assad regime 18 months ago, preventing 60,000 deaths and rise of al-Qaeda. It could still save the larger region from ruin.

The problem here is not that advocates of the Iraq invasion have failed to learn its lessons. It is that opponents of that war, starting with Obama, have learned the wrong ones.

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