San Francisco Bay Area a primary embarkation point for American forces. In 1945, the United Nations Charter was signed in San Francisco, establishing the United Nations, and in 1951, the Treaty of San Francisco officially ended the U.S.'s war with Japan. Since then, the Bay Area has experienced numerous political, cultural and artistic movements, developing unique local genres in music and art and establishing itself as a hotbed of progressive politics. Economically, the post-war Bay Area saw huge growth in the financial and technology industries, creating a vibrant and diverse economy with a gross domestic product of over $800 billion, and home to the
San Francisco International Airport shift all of their service from the airport to Oakland and San Jose. However, Southwest eventually returned to SFO in 2007. A long-planned extension of the Bay Area Rapid Transit (BART) system to the airport opened on June 22, 2003, allowing passengers to board BART trains at the international or domestic terminals and have direct rail transportation to downtown San Francisco, Oakland, and the East Bay. On February 24, 2003, the AirTrain people mover opened, transporting passengers between terminals, parking lots, the BART station, and the rental car center on small automatic trains. SFO became the base of operations for