Yes, people born in the U.S. Virgin Islands (USVI)—which includes St. Thomas, St. Croix, and St. John—are statutory U.S. citizens. This status was granted by the U.S. Congress through the Organic Act of 1954 (and prior legislation in 1927). As U.S. citizens, they can travel freely to the mainland United States without a visa and are entitled to hold a U.S. passport. However, because the USVI is an unincorporated territory, their citizenship comes with certain limitations while they are residing on the islands. For example, USVI residents do not have the right to vote for the President of the United States in the general election, and they do not have voting representation in Congress (they elect one non-voting delegate to the House of Representatives). If a USVI-born citizen moves to one of the 50 states or D.C., they immediately gain full voting rights in federal elections just like any other resident of that state. It is a common point of confusion, but legally, they are just as much "American" as someone born in New York or California, differing only in the specific constitutional rights that apply to the land they live on.