There is no widely known author named "Charles A Willoughby" with a significant body of work.
The person you may be thinking of is Charles A. Willoughby (1892-1963).
He was a military officer who served as Chief of Intelligence for the U.S. Army during World War II. He was known for his controversial role in the intelligence community and his post-war writing, including:
* "Shanghai Conspiracy" (1952): A book detailing his theories about the origins of World War II.
* "The Intelligence War" (1953): A memoir of his experiences in wartime intelligence.
* "The Scarlet Pimpernel of the Orient" (1958): A book about the espionage activities of the Kuomintang during the war.
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