How can we account for our present situation unless we believe that men high in this government are concerting to deliver us to disaster? This must be the product of a great conspiracy, a conspiracy on a scale so immense as to dwarf any previous such venture in the history of man. A conspiracy of infamy so black that when it is finally exposed, its principals shall forever be deserving of the maledictions of all.

Joseph McCarthy (1908–1957) American politician, attorney

“America’s Retreat from Victory: The Story of Gen. George C. Marshall,” speech, US Senate (14 Jun 1951)
    (Source)

Part of a 65,000 word speech given by McCarthy, attacking Sec. of Defense George C. Marshall (and, by proxy, Harry Truman), alleging a string of sinister post-WW2 US diplomatic and military failures, culminating in Truman's firing of Douglas MacArthur.