After the war, Pash served in various military intelligence positions. He served under General Douglas MacArthur in Japan in 1946 and 1947. Thanks to his efforts, the Soviet attempt to gain a foothold in Japan through a local Orthodox Church failed. Instead, Pash organized for the Bishop Benjamin (Basalyga) to arrive in early January 1947 to take the reins, and thus the American Metropoly, rather than the Moscow Patriarchate, secured influence in the region. As a result of this combination, Pash had had a public clash with the Soviet General Kuzma Derevyanko. From 1948 to 1951, he served as a military representative to the Central Intelligence Agency. During this time, he was in charge of a controversial CIA program called PB-7, which had been formed to handle "wet affairs" like kidnappings and assassinations. There is no evidence that he ever carried out any, and denied that he had in testimony before the Church Committee in 1975. He served as Special Forces planning officer with the U.S. forces in Austria from 1952 to 1953. His final postings were back in the United States, as Deputy Assistant Chief of Staff for Intelligence of the Sixth Army from 1953 to 1956), and in the office of the Assistant Secretary of Defense for Guided Missiles in Washington, D.C., from 1956 until his retirement from the Army in 1957. In 1954, he testified in the Oppenheimer security hearing, recounting the misgivings that he had about Oppenheimer in 1943.