Shortly after leaving office, Wallace became the editor of "The New Republic", a progressive magazine. He also helped establish the Progressive Citizens of America (PCA), a progressive political organization that accepted members regardless of race, creed, or political affiliation. Though Wallace was not a member of the PCA, he was widely regarded as the organization's leader and was criticized for the PCA's acceptance of Communist members. In response to the creation of the PCA, anti-Communist liberals established a rival group, Americans for Democratic Action (ADA), which explicitly rejected any association with Communism. Wallace strongly criticized the president in early 1947 after Truman promulgated the Truman Doctrine and issued Executive Order 9835, which began a purge of government workers affiliated with political groups deemed to be subversive. He initially favored the Marshall Plan, but later opposed it because he believed the program should have been administered through the United Nations. Wallace and the PCA were scrutinized by the FBI and the House Un-American Activities Committee, both of which sought to uncover evidence of Communist influence.