Paul Stafford writes that "The impression that "The Art of the Possible" creates, that Rab welcomed the drive away from appeasement after Prague and supported Halifax for leading it, is wholly false". Butler's own papers suggest that he had gone to "greater lengths to meet Hitler's demands than any other figure in the British government" in 1939. His efforts to revoke the Polish guarantee in the summer of 1939 went beyond even Horace Wilson's and it seems doubtful whether he was willing to fight Hitler over Poland at all. Patrick Cosgrave wrote that "Butler did not merely go along with appeasement, he waxed hard, long and enthusiastic for it, and there is very little evidence in public records at the time that he took the slightest contemporary interest in the rearmament programme to which he devotes such emphasis in his memoirs". Jago comments that over appeasement Butler "distorted the facts, grossly misrepresenting his responsibility and attitudes in 1938". Although not the direct cause of his defeats in 1957 or 1963 "it was … always there, the blemish that he could not quite reason away."