Staughton Lynd was incensed. Here was the anti–Vietnam War movement, growing into something that could challenge LBJ’s murderous campaign, and Bayard Rustin — Bayard Rustin! — goes and sullies the largest antiwar protest to date, accusing it of harboring Communist elements. Lynd, a Yale professor and prominent antiwar activist, decided to make his fury public.

“You must know in your heart that your position betrays your essential moralism over the years,” Lynd wrote in an open letter to Rustin in April 1965. “The lesson of your apostasy on Vietnam appears to be that the gains for American Negroes you advise them to seek through coalition within the Democratic Party comes at a price. . . .  The price is to make our brothers in Vietnam a burnt offering on the altar of political expediency.”

Acidic words not exhausted, Lynd took to the pages of Liberation, a radical publication that Rustin himself had helped found, to further excoriate this “labor lieutenant of capitalism” that was in “coalition with the Marines.”