Most of us do bad ideas all the time... like tonight is my Karaoke night, but that's a different story.
The problem in foreign affairs is that what seems like a good idea often turns out to be a bad one.
Chamberlain left the Munich Conference thinking he got a good deal, and Hitler actually thought he got a bad idea because Mussolini talked him down from a war.
Our history is replete with people we armed or helped who later turned on us, going all the way back to Santa Ana in Mexico, who actually turned on us TWICE. After the Texas war in 1836, he was exiled, we helped him get back into Mexico in 1847 to broker only to have him turn on us again. Then we made another deal with him to gain the Gadsen Purchase, and his own people threw him out of office for it. Go figure.
In the 1980's, backing Saddam and the Muhajadeen in Afghanistan probably seemed like safe bets, compared to the Ayatollahs and the Soviets.
Taking Saddam out probably seemed like a good idea, given having to deal with over a decade of his douchebaggery.
Pulling out of Afghanistan seemed like a great idea everyone was behind, until Biden actually did it.
Now, yeah, if left up to me, we'd get the hell out of the middle east, stop supporting anyone over there including the Zionists, and invest the money in energy independence/alternative/renewables.
Public opinion isn't there.