Admitting he was "overruled and worn down," Truman relented and sent an ambassador and made loans available.[233]

Soviet espionage and McCarthyism
Official portrait of President Truman by Greta Kempton, c. 1945
In August 1948, Whittaker Chambers, a former spy for the Soviets and a senior editor at Time magazine, testified before the House Un-American Activities Committee (HUAC). He said an underground communist network had worked inside the U.S. government during the 1930s, of which Chambers had been a member, along with Alger Hiss, until recently a senior State Department official. Chambers did not allege any spying during the Truman presidency. Although Hiss denied the allegations, he was convicted in January 1950 for perjury for denials under oath.
The Soviet Union's success in exploding an atomic weapon in 1949 and the fall of the nationalist Chinese the same year led many Americans to conclude subversion by Soviet spies was responsible and to demand that communists be rooted out from the government and other places of influence.[234][235] Hoping to contain these fears, Truman began a "loyalty program" with Executive Order 9835 in 1947.[236] However, Truman got himself into deeper trouble when he called the Hiss trial a "red herring".