WaPo: "all of the foreign fighters contributing to al-Qaeda’s strength in northern Syria traveled there via Turkey,"

"... For more than a year, Turkey turned a blind eye as thousands of foreign volunteers from across the Muslim world streamed through the country en route to fight alongside Syria’s rebels, perhaps calculating that the fighters would help accelerate President Bashar al-Assad’s demise.Now the extremists whose ranks the foreigners swelled are gaining ascendancy across northern Syria, putting al-Qaeda on NATO’s borders for the first time, raising fears of cross-border attacks and exposing how terribly Turkey’s efforts to bring about Assad’s removal have gone awry.
Meanwhile, in Damascus, Assad is showing every sign that he will ride out the revolt and perhaps remain in power for years, sustained in part by Western alarm at the rise of the extremists. The United States has served notice that it has no intention of intervening militarily, and Turkey, once the most vocal proponent of action to oust Assad, has been left to confront the consequences of what appears to have been a grave policy miscalculation.
“This was not the outcome Turkey wanted,” acknowledged a Turkish official who spoke on the condition of anonymity because the subject of Syria is so sensitive.
Critics say Turkey has only itself to blame for a state of affairs that Turkish authorities appear, at least indirectly, to have encouraged...Almost all of the foreign fighters contributing to al-Qaeda’s strength in northern Syria traveled there via Turkey, flying into Istanbul and transferring to domestic commercial flights for the trip to the border. With their untrimmed beards and their backpacks, the foreigners are often conspicuous in the sedate, Western-oriented towns of southern Turkey....
Some opposition politicians have accused the Turkish government of going further than simply tolerating the traffic, saying that it also has helped transport, train and arm the foreign fighters....Foreign fighters captured by Kurds have claimed that they were trained in Turkish camps and that Turkish instructors teach at rebel camps in Syria, according to Saleh Muslim, the leader of the Kurdish Democratic Union Party, the biggest Kurdish faction in Syria....
Turkey also may not have minded that the foreigners appeared to be contributing to the effort to oust Assad, said Soner Cagaptay of the Washington Institute for Near East Policy.
“Turkey believed so firmly that Assad would fall and the good guys would take over they did not see a problem with allowing anyone and everyone to go and fight,” he said. “But the entire premise is now coming to fruition.”
The realization that both Assad and the jihadists may endure is prompting what one analyst familiar with government thinking called “adjustments” to Turkey’s policy. Ankara is not going to drop its insistence that Assad must go, he said, but it is exploring more nuanced ways to pursue the objective.
Erdogan has softened his once-colorful anti-Assad rhetoric, denounced the al-Qaeda-affiliated groups active in Syria and reached out to some former friends who had been alienated by his staunch support for the Syrian opposition, including Iraq and Iran...."