I believe the United States government's surveillance of the National Committee Against Repressive Legislation did not cease in 1971 as the article implies. I believe I have proof the FBI presses on or some other federal agency picked up and is carrying on.
In 1986, an envelope containing a check I sent to NCARL on April 3 was returned to me bearing a yellow sticker stating "No Forwarding Address on File Unable to Forward." The envelope had been opened and resealed with plastic tape. Inside the envelope with my check to NCARL for my monthly contribution as an NCARL sustainer, was a note from the United States Postal Service, St. Paul, Minn., telling me "If a return address had been on" my mail, it would not have been sent to the dead letter office, etc.
The opened and resealed returned envelope was of the same type NCARL has been using for years, bearing the pre-printed address NCARL has been using for as long as I've known Wilkinson, and is the return address on the package I received from NCARL recently. I don't know where the Postal Service came up with the notion NCARL was no longer at the pre-printed address.