U.S. History, 1942-1953 By Molly Inmon Dec 2, 1942 The Manhattan Project is pursued and studied. Apr 13, 1943 The Jefferson Memorial is dedicated and created. Jun 22, 1944 The G.I. Bill of Rights are established. Jan 2, 1945 Franklin D. Roosevelt becomes president of the United States. Apr 12, 1945 President Roosevelt dies. Dec 4, 1945 The U.S. enters the United Nations. Apr 3, 1948 The Marshall Plan is signed and implemented. Jan 20, 1953 Dwight D. Eisenhower becomes president of the United States.