Potsdam Conference – At Potsdam, the three main Allied leaders hold their final summit of the war. President Truman officially informs Stalin that the U.S. has a powerful new weapon. July 21 – WWII: President Harry S. Truman approves the order for atomic bombs to be used against Japan. July 23 – WWII: French marshal Philippe Pétain, who headed the Vichy government during WWII, goes on trial for treason. July 26 Winston Churchill resigns as Prime Minister of the United Kingdom, after his Conservative Party is soundly defeated by the Labour Party in the 1945 general election. Clement Attlee becomes the new Prime Minister. It is the first time that Labour has governed Britain with a majority in the House of Commons. The Potsdam Declaration demands Japan's unconditional surrender; Article 12, permitting Japan to retain the reign of the Emperor, has been deleted by President Truman. July 27 – WWII: Bombing of Aomori – Two USAAF B-29s drop a total of 60,000 leaflets on the city of Aomori, Japan, warning civilians of an air raid and urging them to leave immediately. July 28 - WWII: Japan ambiguously rejects the Potsdam Declaration. July 29 The BBC Light Programme radio station is launched in the United Kingdom, aimed at mainstream light entertainment and music. WWII: Bombing of Aomori: The Japanese city of Aomori is firebombed by 63 USAAF B-29 heavy bombers, killing 1,767 civilians and destroying 18,045 homes. July 30 – WWII: Heavy cruiser is hit and sunk by torpedoes from the in the Philippine Sea. Some 900 survivors jump into the sea and are adrift for up to four days. Nearly 600 die before help arrives. Captain Charles B. McVay III of the cruiser is later court-martialed and convicted; in 2000, he is posthumously exonerated. August August 6 – WWII: Atomic bombing of Hiroshima: United States Boeing B-29 Superfortress Enola Gay drops a uranium-235 atomic bomb, codenamed "Little Boy", on the Japanese city of Hiroshima at 8:15 a.m. local time, resulting in between 90,000 and 146,000 deaths. August 7 – U.S. President Harry Truman announces the successful atomic bombing of Hiroshima, while he is returning from the Potsdam Conference aboard the U.S. Navy heavy cruiser , in the middle of the Atlantic Ocean. August 8 The United Nations Charter is ratified by the United States Senate, and this nation becomes the third to join the new international organization. WWII: The Soviet