I'm not sure how that is supposed to be "bad", other than in retrospect. At the time, the Mujahadeen were considered to be the legitimate opposition to the Soviets.
The Reagan administration supported Saddam in the Iran-Iraq war. Again in retrospect, that doesn't appear to have been a wise choice, but at the time it seemed to be the right thing to do at the time.
We had an (albeit uneasy) alliance with Stalin in WWII, as well.
All are examples of the old saying: "the enemy of my enemy is my friend". Joining together against a common enemy doesn't always signify mutual agreement on everything.
Still, I really wonder what happened in the incident I noted in the blog posting. People really should team up with a friend and invest in a video camera and a wireless mike before confronting someone over politics or religion.
From what I’ve read, it boils down to Brzezinski supporting Carter’s decision to throw the Shah of Iran under the bus, which led to the Islamofascists taking Iran in 1979. Also, a general perception that he showed streaks of anti-semitism regarding Carter’s Middle East policies and that those attitudes continue to this day.