US President Joe Biden addresses a press conference with Japanese Prime Minister Fumio Kishida in Tokyo – Copyright AFP Ludovic MARIN Shaun Tandon with Amber Wang in Taipei With a warning to China that the United States will defend Taiwan, President Joe Biden has offered the island its loudest reassurance in decades but brought more uncertainty to a US stance designed to be ambiguous. On a visit to Tokyo, Biden gave an unequivocal yes when asked if the United States would defend Taiwan in an invasion by China, which claims the self-governing democracy off its coast as its own. “That’s…