For me, this is the most important paragraph in the article. It best accords with my personal experience.
"Useful idiots" see only the flaws in American society and will uncritically rush to the side of anyone claiming to do better. Not too different from those who buy "miracle cures" from telemarketing hucksters.
The collapse of the Soviet bloc has now made it clear that these useful idiots were not pro-Communist. They were and still are anti-American.