President Donald Trump’s abrupt decision to withdraw U.S. forces from Syria yielded bipartisan criticism, and rightly so. The campaign against ISIS in Iraq and Syria has made substantial progress, but it is not quite over, as evidenced by the fact that the U.S. military took, on average, 30 airstrikes per day against ISIS targets in the first half of December. Announced with apparently no warning to anyone outside the White House, the decision is a betrayal of our coalition partners as well as the Syrian Democratic Forces (SDF), who have done most of the fighting and dying on the ground in Syria against ISIS.

Several commentators couldn’t resist comparing Trump’s action with President Obama’s decision to withdraw American forces from Iraq in 2011. While superficially similar, the two cases are far from identical. Understanding their differences helps to show what makes President Trump’s action so dangerous.

Reasons for full withdrawal

The seeds of the American withdrawal in 2011 were sown by the architect of the Iraq War, President George W. Bush. In 2008, as he neared the end of his term, Bush negotiated two agreements with Iraq in an attempt to build a framework for a lasting U.S. commitment. One of these, a status of forces agreement (SOFA), explicitly provided that all U.S. forces would “withdraw from all Iraqi territory no later than December 31, 2011.” That building block was in place before President Obama’s national security team ever stepped foot in the White House. President Obama, of course, campaigned against the war, and ordered an orderly drawdown, consistent with the SOFA, soon after taking office. He agreed, nonetheless, to leave a small residual force of 5,000 troops but failed to reach agreement with Iraq over immunity protections for U.S. forces.

It was not for lack of trying. I worked for Vice President Biden at the time; he had Iraqi political leaders on speed-dial and traveled to Iraq multiple times in the first Obama term. For his part, President Obama spoke or met with Prime Minister Maliki three times in 2011. The politics were just too hard for the leaders in Baghdad, who were highly sensitive to sovereignty concerns after eight years of a sizable American presence.

Cost-benefits of maintaining a small U.S. force

It’s debatable that a small U.S. force could have prevented the rise of ISIS in 2014. The U.S. Ambassador to Iraq in 2011, Jim Jeffrey (now Trump’s special envoy for Syria and who also served as Bush’s deputy national security adviser) well understands the complexity of Iraq, disputed that notion at the time:

Could a residual force have prevented ISIS’s victories? With troops we would have had better intelligence on al Qaeda in Iraq and later ISIS, a more attentive Washington, and no doubt a better-trained Iraqi army. But the common argument that U.S. troops could have produced different Iraqi political outcomes is hogwash. The Iraqi sectarian divides, which ISIS exploited, run deep and were not susceptible to permanent remedy by our troops at their height, let alone by 5,000 trainers under Iraqi restraints.

Maintaining political and economic engagement

In contrast to Trump’s decision to withdraw all U.S. forces as well as political and reconstruction teams from Syria, the Obama administration remained engaged in providing political and economic support to Iraq after 2011, pursuant to the other bilateral accord that Bush signed in 2008, a strategic framework agreement. U.S. government data indicates that we provided $2 billion in U.S. foreign assistance in 2012, though aid was scaled back in subsequent years. And we maintained a large Embassy in Baghdad, with consulates in Basra and Irbil.

Militarily and politically recalibrating to meet the ISIS threat

In the summer of 2014, when ISIS emerged as a mortal threat to the Iraqi state, President Obama quickly authorized U.S. military action and re-supply to Iraqi forces to protect Baghdad and Erbil. He then insisted on a more inclusive national government before committing to a broader counter-ISIS campaign, given that ISIS found fertile ground in the Sunni regions that had been substantially ignored by the Shiite politicians dominant in Baghdad. The military campaign conceived that summer focused on working by, with, and through partners in Iraq and Syria, who have done the bulk of the fighting on the ground. In support, the U.S. and coalition partners provided air power and intelligence, and armed and trained the local partners. Small contingents of U.S. forces on the ground provided advice and engaged in targeted raids. Far from disengaging, President Obama understood that the United States had an obligation to support the democratic government in Iraq, and our partners in Syria.

No comparison

Compare all of that with President Trump’s apparent abandonment of the local forces – the SDF — who expelled ISIS from eastern Syria. The SDF enlisted in the fight not only to take back their towns, but in reliance upon assurances provided during both the Obama and Trump administrations that U.S. support would continue after the war. Part of that commitment was a promise to give them a seat at the table on the political future of Syria; our ability to deliver on that pledge is now in question. Suddenly vulnerable to hostile Turkish forces, the SDF, in particular its Kurdish element, will likely need to cut a deal with the Assad regime. In short, our small military force provided outsized political and military benefits. The cost to U.S. credibility will resonate for years in the region, and perhaps beyond.

We’ve also left many other partners holding the bag. The Defeat-ISIS coalition now consists of over 70 countries and international organizations. As with so many international security challenges, it required U.S. leadership to build and sustain, which was provided over the last four and one-half years by senior officials at the National Security Council and the Departments of State and Defense. A wholesale and sudden retreat from Syria, announced to our closest allies by an impetuous tweet, is no way to maintain the trust required to lead a large multilateral alliance.

To be sure, Presidents Obama and Trump share a belief that we are over-invested in the Middle East. There the comparison ends, and it’s facile to suggest otherwise.

Image credit: (L) President Barack Obama arrives in White House press briefing room on October 21, 2011 to announce withdrawal of all US forces from Iraq (Jim Watson/AFP/Getty Images).