It's worth remembering that Al Qaeda in Syria (under various other names) was funded and armed by the United States, Britain, Jordan, Turkey, Saudi Arabia, and Qatar according to numerous published reports, and that fighters for the organization were trained at secret CIA/military bases in Jordan and Turkey, and that the CIA operation in Libya in coordination with Qatar (out of Benghazi) funneled Libyan weapons to the organization for use against the Syrian government.
For example:
"Arming Syrian rebels: Where the US went wrong 10 October 2015 BBC"
> "Those who supported his approach, the Arms for Rebels group, included then-CIA Director David Petraeus, then-Secretary of State Hillary Clinton and most of the foreign-policy establishment in Washington, both Democrat and Republican."
"Behind the Sudden Death of a $1 Billion Secret C.I.A. War in Syria (2017)"
> "...some of the C.I.A.-supplied weapons had ended up in the hands of a rebel group tied to Al Qaeda..."
Seems to be a pattern of behavior dating back to the Cold War, when the CIA decided that supporting violent religious fundamentalists in the Middle East and elsewhere would provide a bulwark against the Godless Communists.
For example: "Arming Syrian rebels: Where the US went wrong 10 October 2015 BBC"
https://www.bbc.com/news/magazine-33997408
> "Those who supported his approach, the Arms for Rebels group, included then-CIA Director David Petraeus, then-Secretary of State Hillary Clinton and most of the foreign-policy establishment in Washington, both Democrat and Republican."
"Behind the Sudden Death of a $1 Billion Secret C.I.A. War in Syria (2017)"
https://www.nytimes.com/2017/08/02/world/middleeast/cia-syri...
> "...some of the C.I.A.-supplied weapons had ended up in the hands of a rebel group tied to Al Qaeda..."
Seems to be a pattern of behavior dating back to the Cold War, when the CIA decided that supporting violent religious fundamentalists in the Middle East and elsewhere would provide a bulwark against the Godless Communists.