WASHINGTON—Former Senator Chris Dodd and former Deputy Secretaries of State Richard Armitage and James Steinberg headed to Taiwan on Tuesday at President Joe Biden’s request. A senior Biden administration official told Reuters the dispatch of the “unofficial” delegation comes as the United States and Taiwan mark the 42nd anniversary of the Taiwan Relations Act, for which Biden voted when he was a U.S. senator. The delegation will meet with senior Taiwanese officials and followed “a long-standing bipartisan tradition of U.S. administrations sending high-level, unofficial delegations to Taiwan,” the official said. The official called it “a personal signal” from the president, who took office in January. “The selection of these three individuals—senior statesmen who are longtime friends of Taiwan and personally close with President Biden—sends an important signal about the U.S. commitment to Taiwan and its democracy.” Taiwan’s presidential office said President Tsai Ing-wen would meet with the delegation on Thursday …