Pakistan, May 16 -- At first glance, it had the staging of an old wartime rendezvous: two leaders moving through guarded grounds, the cameras held at a careful distance, the gardens doing the work of diplomacy before the documents could. One could almost imagine a distant echo of Roosevelt and Churchill, except that this was not an alliance being drafted in the shadow of war.

US President Donald Trump and Chinese President Xi Jinping walked through the rosebushes and manicured paths of Zhongnanhai, the walled leadership compound at the centre of Chinese power. The setting was intimate by the standards of Chinese statecraft, and that was precisely the point. Rare access was itself a message. Trump, admiring the roses and Xi, offering to s...