“A merican strength back on the world stage,” crowed the White House social media post: a curious remark, when the attached video showed the stars and stripes fluttering beneath a long row of Chinese flags, and People’s Liberation Army soldiers marching in unison. This week’s visit to Beijing offered the kind of style that Donald Trump enjoys – parading troops, a banquet and a polite if not markedly enthusiastic welcome from a strongman he called “really a friend” – but little apparent substance. The public account of the encounter will be partial: Mr Trump’s former adviser John Bolton has claimed that in previous conversations the US president begged Xi Jinping for help to win re-election and urged him to “go ahead” with internment camps for Uyghurs in Xinjiang. But this meeting appears to have been about stabilising the relationship , not shifting it. Chaotic US planning for a trip deferred due to the Iran war may have contributed to the lack of tangible outcomes.…