Sen. Lindsey Graham (R-S.C.) at a Capitol Hill news conference on Dec. 20 addressing President Trump's announced decision to withdraw U.S. troops from Syria. (Win McNamee/Getty Images) (Win Mcnamee/Getty Images)

In the wake of President Trump’s announcement that he intends to quickly withdraw U.S. military forces from Syria, the who-lost-Syria debate has quickly ratcheted up — much as it did when critics cited President Barack Obama’s “indecision” as the reason U.S. Syria policy “fell apart.”

The reaction from members of the president’s party in Congress was immediate and harsh. Sen. Lindsey Graham (R-S.C.) said: “An American withdrawal at this time would be a big win for ISIS, Iran, Bashar al Assad of Syria, and Russia. I fear it will lead to devastating consequences for our nation, the region, and throughout the world.” Similarly, Sen. Marco Rubio (R-Fla.) tweeted: “The decision to pull out of Syria was made despite overwhelming military advice against it. It is a major blunder. If it isn’t reversed it will haunt this administration & America for years to come.”

But Trump’s decision didn’t cause the U.S. to lose in Syria. For all practical purposes, Syria was already lost. Much like his predecessor, Trump’s decision is motivated by a calculation that the U.S. can’t alter the military or political balance in Syria that has long favored Russia and Iran. The timing of the president’s announcement is unfortunate, as is his apparent failure to consult with allies and Congress before making it. But Trump was right about one thing. With a modest military footprint and little public support for a larger American role, the U.S. can’t really compete with Russia or Iran on the ground.

Trump said back in March that “We’re knocking the hell out of ISIS. We’ll be coming out of Syria, like, very soon.” Not only was he engaged in wishful thinking — indeed, at a press briefing this week, a State Department spokesman said “the job is not yet done” — taking action now based on that sentiment likely makes the goal of wiping out the Islamic State more difficult to achieve in the future.

Trump’s string of withdrawal tweets and accompanying video were all music to Russian President Vladimir Putin’s ears — Putin calling Trump’s decision “correct” pretty much confirms this. The same goes for the Iranian regime, which, like Putin, considers Syrian President Bashar al Assad a client. Ditto leaders in Turkey — a NATO member whose Syria aims don’t sync with ours.

And it’s fair to assess that Trump’s hasty declaration was the final straw leading up to Defense Secretary Jim Mattis’s resignation Thursday, complete with Mattis’s stinging sign-off to Trump that “you have the right to have a Secretary of Defense whose views are better aligned with yours.” Mattis’s exit will probably have wider, possibly grim, national security implications.

But it should have been clear by now to Graham, Rubio and anyone else that Moscow and Tehran had long ago won the strategic fight for Syria. Russian military intervention in 2015 saved Assad and secured long-term military basing rights for the Russian military. As Steven Cook observed in July, Syria is “the centerpiece and pivot of Russia’s strategy to reassert itself as a global power.” Iran, in its long-term effort to gain regional power and further its proxy war against, among others, rival Saudi Arabia, has lent Assad the assistance of the Iranian military and Iran-backed Shiite militias. Though a predominantly Sunni country like Saudi Arabia, Turkey shares Shiite-dominated Iran’s goal of thwarting anything that bolsters Kurdish autonomy, including close military cooperation between the U.S. military and Kurdish forces in Syria and Iraq.

To achieve their ends, Russia and Iran have been more willing to devote resources toward keeping Assad afloat than the U.S. has been prepared to either remove him from power or stand behind the assorted elements in Syria who’ve tried and so far failed to overthrow him. There are valid reasons for U.S. reticence, but Americans should let go of the idea that we were ever trying very hard to win.

The core U.S. security interest in Syria is denying the Islamic State a geographic base from which to conduct terrorist violence. And under both Obama and Trump, U.S. forces with Kurdish allies have succeeded in taking back most of territory that the Islamic State once held and tens of thousands of the Islamic State’s fighters in Iraq and Syria. But the threat hasn’t been totally neutralized.

The Islamic State can’t be defeated once and for all by military means alone because it is driven by political, economic and sectarian grievances that can only be alleviated by better governance. On its own, the Syrian government has neither the motivation nor the means to substantially address these grievances or to reconstruct areas liberated from Islamic State control. The U.S. has the means, but not the will. The roughly 2,000 U.S. troops and the handful of American diplomats in Syria were insufficient to the task, and the eagerness to get out, articulated by Trump, is inconsistent with the reality that staying could mean remaining for decades to rebuild, or at least stabilize, Syria. Earlier this year, when the Trump administration held back $200 million allocated for Syria reconstruction, it sent a message that there was no U.S. appetite for investing in Syria beyond immediate military containment of Islamic State forces.

As long as the U.S. military has been engaged in the fight against these Islamic State forces, Russia, Iran and Turkey have been happy to let Americans make this sacrifice. And aside from ensuring that the various parties to the Syria conflict, including Hezbollah, stay away from the Golan Heights, Israel has played a relatively minor role in the anti-Islamic State campaign. But any of these countries are certainly capable of providing a military counterweight to the Islamic State — the question is what will come of the region when the United States really does leave. There’s no guarantee that Russia or Iran, which share a common interest in seeing the Assad regime survive, will step up once we’ve left. In contrast to the U.S., however, if and when Syria and its backers decide to conclusively take on the Islamic State, their approach is unlikely to employ much regard for humanitarian concerns or civilian lives. Syria, already an overwhelming human tragedy, could easily see even more death and destruction.

Critics of the president’s decision are right that the U.S. is once again going to throw its reliable Kurdish allies under the bus. But the Kurds could have foreseen this, both because of their previous experiences with the U.S. in Iraq and Trump’s chronic unhappiness with the Syria deployment. As Ambassador James Jeffrey, now the administration’s envoy for Syria, told the New York Times in January, “We told the Turks that the Kurds were temporary, tactical, and transactional to defeat ISIS.”

The Syrian Democratic Forces, or SDF, a militia comprised mainly of Kurdish and Arab fighters, has ties to a Syrian Kurdish political party that, in turn, has ties to the Kurdistan Worker’s Party, or PKK, one of Turkey’s nemeses. Syrian Kurds aren’t fighting as a favor to the United States. They seek to establish an autonomous Kurdish enclave in Northeast Syria, which could ultimately bring the U.S. into a larger conflict with Turkey.

Eventually, continued U.S. support for the SDF might have led to an independent Kurdish polity and the need to protect it. With Turkey as a formal U.S. ally, that expectation was always unrealistic. The appropriate course, leading up to withdrawal from Syria, would have been for the Trump administration to offer Syrian Kurds incentives to reach an accommodation with Assad and Turkish President Recep Tayyip Erdogan to preserve as many of their gains as possible.

Syria’s civil war has resulted in hundreds of thousands of deaths, created millions of refugees and emboldened a self-styled caliphate that sponsors global terrorist violence. The timing and the implementation of Trump’s decision to withdraw from this failed state is unwise from the narrow perspective of continuing to degrade the Islamic State, but in many ways it reflects the lack of desire that he, his predecessor, Congress and the American people have for assuming responsibility to resolve the crisis. It’s hard to make the case that it’s worth American blood and treasure to maintain an open-ended deployment there to accomplish goals that are beyond our capacity to achieve. Trump’s withdrawal will make the fight against the Islamic State harder. Still, there’s no point pretending: We’ve never been willing to expend the resources necessary to have real leverage that would give us a meaningful capacity to compete with the countries that do.