Syrian emergency personnel and civilians carry a body following a reported barrel bombing in the Maysar neighbourhood of the northern Syrian city of Aleppo on July 10, 2014. (Khaled Khatib/AFP/Getty Images)

The Obama administration’s decision to seek $500 million to train and fund elements of the Syrian opposition has been greeted with bipartisan support in Washington. The general consensus is that, if the administration had done this three years ago, the situation in Syria would not have turned into a sectarian civil war. But this conventional wisdom is wrong. The administration is caving in to the classic Washington desire to “do something” in the face of a terrible situation without any clear sense as to whether it would improve things or make matters worse.

“The Syrian people started this revolution through peaceful demonstrations,’’ said Sen. Lindsey Graham (R-S.C.) — one of many to make the case that the struggle has turned sectarian because Washington was passive while it grew more intense. “These radical Islamists are hijacking the revolution,” Graham explained.

In fact, radical Islamists have been the core of the opposition to the Assad regime from the very beginning, decades ago. Bashar al-Assad’s father, Hafez al-Assad, came to power in a coup in 1970 and was the first non-Sunni to rule the country. By the late 1970s, he faced an armed Islamist insurgency that spread across the country’s major cities. Between 1979 and 1981, it killed more than 300 supporters of the regime in Aleppo alone. Assad, in turn, ordered crackdowns that killed some 2,000 Islamist opponents.

Eugene Rogan’s book “The Arabs: A History” recounts the story of a young Alawite commander during those years, Isa Ibrahim Fayyad, who was sent on his first mission to the Tadmur prison. “They opened the gates of a cell block for us. Six or seven of us entered and killed all those we found inside, some 60 or 70 people in all. I must have gunned down 15 myself. . . . Altogether some 550 of those Muslim Brother bastards must have been killed.”

The Islamists’ terror campaign spread, moving even to Damascus, where in November 1981 they exploded a car bomb in the city center that killed 200 people and wounded 500. Then, in 1982, came the uprising and the gruesome massacre in the town of Hama, where between 10,000 and 20,000 people — including women and children — were slaughtered by government troops. Since then, the regime has organized itself for war against the Islamists and they, in turn, have been preparing for opportunities to wage war against the regime.

Syria has been unstable from its birth. Between its independence in 1946 and Assad’s coup, there were around 10 other coups and attempted coups. By the late 1970s, it was already divided into camps, largely defined by Islamism and sect. Outside powers in the Middle East — Saudi Arabia, Iraq, Iran — have been funding, arming and training militants on both sides. In 2011, these long-simmering tensions bubbled over.

Today, according to James Clapper, the director of national intelligence, there are about 1,500 separate insurgent groups in Syria, with between 75,000 and 115,000 insurgents. In addition, there are 7,500 foreign fighters from neighboring countries. The strongest groups are all radical Islamist — the Islamic State, Ahrar al-Sham and Jabhat al-Nusra.

Remember that neighboring powers, like the Turkish government, spent months trying to establish a moderate Syrian opposition. I met with some of its leaders in Istanbul in 2012. They were genuinely liberal and democratic people. Unfortunately these people barely had contact with, let alone influence over, the actual groups fighting in Syria. Turkey’s efforts collapsed, as did those of other countries.

But now, Washington is going to “vet” this vast, dispersed opposition of 1,500 groups and find moderates. Good luck. The complexity of Washington’s task can be seen in the American attitude toward the Islamic State. When the group battles the Maliki government in Iraq, it is a deadly foe and must be ruthlessly attacked. But when it crosses the (now-nonexistent) border between Iraq and Syria and battles the Assad regime, it is aligned with America’s stated goal of regime change in Damascus. No other country has this strategic incoherence. The Sunni groups are battling what they see as apostate regimes in Baghdad and Damascus. Those Shiite and quasi-Shiite regimes are being supported by the region’s Shiite powers — Iran and Hezbollah. America alone is searching for the good guys.

With this history in mind, it is difficult to believe that three years ago a modest American intervention of arms and training would have changed the trajectory of events in Syria. But can anyone now believe that a modest American intervention is going to find genuine democrats in the maelstrom, help them win against Assad and also the radicals, and stabilize Syria? Or is Washington’s new activism more likely to throw fuel onto a raging fire?

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