Members of the Syrian Democratic Forces (SDF), an alliance of Kurdish and Arab fighters, drive on the western front in Raqqa, Syria, during an offensive by the SDF to retake the city from Islamic State fighters. (Bulent Kilic/Agence France-Presse via Getty Images)

What did the CIA’s covert assistance program for Syrian rebels accomplish? Bizarrely, the biggest consequence may be that it helped trigger the Russian military intervention in 2015 that rescued President Bashar al-Assad — achieving the opposite of what the program intended.

Syria adds another chapter to the star-crossed history of CIA paramilitary action. These efforts begin with the worthy objective of giving presidents policy options short of all-out war. But they often end with an untidy mess, in which rebels feel they have been “seduced and abandoned” by the promise of U.S. support that disappears when the political winds change.

One Syrian opposition leader highlighted for me the danger for his rebel comrades now: “The groups that decided to work with the U.S. already have a target on their back from the extremists, but now will not be able to defend themselves.”

The demise of the Syria program was disclosed by The Post this week, but it’s been unraveling since President Trump took office. Trump wanted to work more closely with Russia to stabilize Syria, and a program that targeted Russia’s allies didn’t fit. The White House’s own Syria policy remains a hodgepodge of half-baked assumptions and conflicting goals, but that’s a subject for another day.

The rise and fall of the Syria covert action program conveys some useful lessons about this most delicate weapon in the United States’ arsenal. To summarize, the program was too late, too limited and too dependent on dubious partners, such as Turkey and Saudi Arabia. It was potent enough to threaten Assad and draw Russian intervention, but not strong enough to prevail. Perhaps worst, the CIA-backed fighters were so divided politically, and so interwoven with extremist opposition groups, that the rebels could never offer a viable political future.

That’s not to say that the CIA effort was bootless. Run from secret operations centers in Turkey and Jordan, the program pumped many hundreds of millions of dollars to many dozens of militia groups. One knowledgeable official estimates that the CIA-backed fighters may have killed or wounded 100,000 Syrian soldiers and their allies over the past four years. By the summer of 2015, the rebels were at the gates of Latakia on the northern coast, threatening Assad’s ancestral homeland and Russian bases there. Rebel fighters were also pushing toward Damascus.

CIA analysts began to speak that summer about a “catastrophic success” — in which the rebels would topple Assad without creating a strong, moderate government. In a June 2015 column, I quoted a U.S. intelligence official saying, “Based on current trend lines, it is time to start thinking about a post-Assad Syria.” Russian President Vladimir Putin was warily observing the same trend, especially after an urgent visit to Moscow in July that year by Maj. Gen. Qasem Soleimani, commander of Iran’s Quds Force and Assad’s regional patron.

Putin got the message: He intervened militarily in September 2015, decisively changing the balance of the Syrian war. What Trump did in ending the CIA program was arguably just recognizing that ground truth.

What could the United States have done to provide a different outcome? Here are some thoughts gathered from U.S. and Syrian officials who have followed the CIA program closely.

●CIA support could have started earlier, in 2012, when extremists weren’t so powerful and there was still hope of building a moderate force. By 2013, when the program got rolling, the military opposition was dominated by jihadists and warlords.

●The United States could have given the rebels antiaircraft weapons, allowing them to protect rebel-held areas from Assad’s brutal bombing. The rebels trained with such weapons but could never use them on the battlefield.

●While negotiating the nuclear deal with Iran, the United States didn’t want to kill Iranians in Syria. And once Putin intervened, the United States avoided Russians. Those limits were prudent, but they neutered the U.S.-backed military operations.

●The United States didn’t have a political strategy to match the CIA’s covert campaign. “There was no ‘there’ there, in terms of a clearly articulated national security objective and an accompanying strategy,” said Fred Hof, a former State Department official who has followed the Syria story closely. The American effort unintentionally “created massive divisions and rivalries instead of being used as a tool to unite disparate factions,” another former official said.

Contrast the sad demise of the CIA’s anti-Assad program in western Syria with the rampaging campaign against the Islamic State in the east. What’s the difference? In the east, motivated, well-organized Syrian fighters are backed by U.S. warriors on the ground and planes in the sky. In this game, halfway is not the place to be.

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