In the days of J. Edgar Hoover, the FBI worked hard on the Communists and it was said when they held a meeting in the late 1950’s, half the room was FBI.
Hoover’s anti-communism gained him the lifelong contempt of the Left, who ended up smearing him as a gay man.
Perhaps President Trump can re orient their priorities more appropriately.
In the 1970’s, the conventional wisdom among anti-war groups was that the person pushing for the most illegal and radical action was the government informant.