11, 1899. Guam is among the 17 nonself-governing territories listed by the United Nations. World War II Before World War II, five American jurisdictions were in the Pacific Ocean: Guam and Wake Island in Micronesia, American Samoa and Hawaii in Polynesia, and the Philippines in Southeast Asia. On December 8, 1941, hours after the attack on Pearl Harbor, Japanese forces from the Marianas launched an invasion of Guam. Chamorros from the Northern Marianas, who had been under Japanese rule for more than 20 years, were brought to Guam to assist the Japanese administration. This, combined with the harsh treatment of Chamorros during the two-and-a-half-year occupation, created a rift that would become the main reason Chamorros rejected the referendum on reunification approved by the Northern Marianas in the 1960s. During the occupation, Chamorros were subjected to forced labor, incarceration, torture, and execution. American forces recaptured the island on July 21, 1944; Liberation Day commemorates the victory. After World War II, the Guam Organic Act of 1950 established Guam as an unincorporated organized territory of the United States, provided for the structure of the island's civilian government, and granted the people U.S. citizenship. The governor of Guam was federally appointed until 1968, when the Guam Elective Governor Act provided for the office's popular election. Since Guam is not a U.S. state, U.S. citizens residing on Guam are not allowed to vote for president and their congressional representative is a nonvoting member. They do, however, get to vote for party delegates in presidential primaries. The increasing numbers of Chamorros, especially Chamorro youth, relocating to the U.S. mainland, has complicated both definition and preservation of Chamorro identity. On Guam, a Chamorro-rights movement has developed since the United States gained control of the island. Leaders of the movement seek to return ancestral lands to the Chamorro people, and attain self-determination. Modern Chamorro culture Chamorro culture has over the years acquired noticeable influences from Spanish, Mexican, American, Japanese, and Filipino cultures, as well as the presence of fellow Oceanic (mostly Micronesian) groups. Influence from the German era in the Northern Marianas is most visible in the form of certain given names and family surnames. The prehistoric concept of inafa'maolek ("doing good for each other", often translated as interdependence) is a core value of traditional Chamorro culture. Respect for one's family, community, and the elderly (man åmko''') are major components, although this varies from person to person