The Syrian government and its allies, including Iran, will eventually overcome U.S. efforts to secure influence in the nation, and Kurdish fighters may pay for siding with President Donald Trump and his administration, according to a former U.S. ambassador to Syria.

Robert Ford, who served as envoy to Syria under former President Barack Obama from 2011 through 2014, said during an interview Monday with the London-based Arabic-language newspaper Asharq Al-Awsat that "Obama did not leave the Trump administration many options to achieve its goal" of defeating the Islamic State militant group (ISIS) and curbing Iran's foothold in the region. While Iran and Russia back Syrian President Bashar al-Assad against various insurgents and jihadists trying to topple him, the U.S. supports an irregular coalition, the Syrian Democratic Forces, made up mostly of Kurds, but including other ethnic minorities and Arabs. Despite the group's recent successes in storming ISIS's de facto capital of Raqqa, Ford said "the game was finished" for U.S. plans to overthrow Assad or compete with Iran's success in the country.

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"The Iranian position will advance," Ford said, offering his prediction for what the battle lines may look like in the next few years: Assad retaining his stronghold in the west, and Iran bolstering pro-government forces that he predicted would ultimately force a U.S. withdrawal from eastern Syria—much like the Iran-backed, Shiite Muslim militant group Hezbollah managed to do in Lebanon in the 1980s.

"Assad won, I mean he's the victor, or he thinks so," Ford told the newspaper, suggesting that the Syrian leader was unlikely to face any charges stemming from war crime accusations by the West. "Maybe in 10 years, he will retake the entire country."

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Syrian Arab News Agency/Reuters

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Ford spoke candidly about what he believed were serious errors made by Washington at the beginning of the crisis in Syria, in 2011. He recalled being deeply opposed to Obama and then-Secretary of State Hillary Clinton's decision to publicly call for Assad's removal from power during a period of mass demonstrations against the Syrian government. He said he knew that U.S. approval for the political opposition would encourage certain elements to take up arms against the government, expecting the U.S. military to stage an Iraq-style intervention to aid them—which he did not believe the U.S. would carry out.

When the opposition, which also received support from Turkey and Gulf Arab states such as Saudi Arabia and Qatar, did launch a large-scale insurgency against the state, the CIA ultimately decided to train and equip certain rebel groups. After this policy came to light, Ford said in 2014 that the U.S. was "behind the curve," as Russia and Iran were devoting extensive resources to defending Assad, much more than the U.S. was willing to devote to the insurgents, Many of the insurgents were later overtaken or absorbed by more radical Sunni Muslim militant moves such as ISIS and Al-Qaeda.

As jihadists climbed the ranks among Syrian rebels, the U.S. shifted the focus of its policy toward eradicating ISIS and began backing another faction, the Syrian Democratic Forces. Many Kurds were initially supportive of the uprising against Assad, hoping it would give them an opportunity to establish an autonomous Kurdish area in northern Syria, much like Iraqi Kurdistan. The mostly Kurdish Syrian Democratic Forces, however, found themselves clashing with both ISIS and Syrian rebel groups backed by Turkey, which has long sought to quell Kurdish nationalism in the region.

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Rodi Said/Reuters

The Syrian Democratic Forces were mostly neutral in the battle between pro- and anti-Syrian government forces, but tensions have risen between the U.S. and pro-Syrian government forces that now share extensive front lines since ISIS's collapse on multiple fronts. Recent clashes between the Syrian army and the Syrian Democratic Forces were followed by the U.S.'s unprecedented decision to shoot down a Syrian military jet it claimed was operating too close to positions held by the Syrian Democratic Forces. Siding with the U.S,, however, will turn out to be a grave mistake for the Kurds, according to Ford. He said U.S. support for Kurds would disappear, as it did in post-invasion Iraq, after ISIS was defeated in Raqqa and in other areas.

"[The U.S.] will not defend the Kurds against Assad's forces," the former envoy said. "What we're doing with the Kurds is not only politically stupid, but immoral."

"Syrian Kurds are making their biggest mistake in trusting the Americans," he added.

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