I bet they'd never make the mistake of arming far-right extremists ever again, though!
Anyone knows an article like this about US supporting Islamic extremists that has citations?
Sure, read any history articles talking about the war in the Middle East during From 1979 to 1989 and you'll find cited references. It was a big part of the war, and not hidden or anything.
The Middle East was siding with the Soviets so the US-funded far-right extremists, the Mujahideen, who eventually because the far-right groups we know today.
This history magazine has some decent citations in it. http://www.historyisnowmagazine.com/blog/2021/3/7/how-america-supported-the-anti-soviet-mujahideen-rebels-in-1980s-afghanistan
But honestly, it shouldn't be too hard for you to find out about it yourself from any historical source.