As Eisenhower let out, a main feature of U.S. state-monopoly capitalism circa 1960 was the military-industrial complex. I believe Comrade Henwood has writen about "military Keynesianism". In signing a nuclear test ban treaty with the Soviet Union, Kennedy may have cost the complex billions of dollars of potential profits. This was enough of a screwup to get the president of the American "corporation" fired, literally and figuratively by this major shareholder bloc. This is the core of the systematic capitalist, not conspiratorial, explanation for the assassination of Kennedy.
CB