US President Donald Trump is meeting US Ambassador to China David Perdue at his Mar-a-Lago estate in Florida on Friday, rounding off a day of diplomacy that began with a call with Japanese Prime Minister Sanae Takaichi. The engagements come at a delicate moment for the administration as it seeks to align its “America first” regional approach amid a deepening diplomatic rift between Tokyo and Beijing over Taiwan, and following Washington’s recent approval of its largest-ever arms sale to the...