St. Thomas is an idyllic island destination in the eastern Caribbean and one of just a few places that United States citizens can travel to in the region without a passport. That’s because St. Thomas — along with St. Croix and St. John — make up the U.S. Virgin Islands, a U.S. territory in the Caribbean. Visitors to St. Thomas won’t find overwater bungalows, but they can still look forward to white-sand beaches, a laid-back vibe and water activities like snorkeling and scuba diving, not to mention duty-free shopping. It’s worth considering for all types of travelers, from those looking for the best family beach vacation to newlyweds searching for…