Japan's prime minister vowed Saturday to do more to ensure a "free and open Indo-Pacific", using a speech in communist Vietnam to tout a regional strategy that has long rankled neighbouring China. "I am renewing my determination to fulfil Japan's responsibilities and… to play an even more proactive role than ever before in building an international order based on freedom, openness, diversity, inclusiveness, and the rule of law," Sanae Takaichi said in an address at a Hanoi university. In an era of "intensifying geopolitical competition, accelerating technological innovation", the Japanese premier called for Asian countries to cultivate "resilience" and the…