This week is a moment of truth for Xi Jinping on deflation

WHEN PRESIDENT DONALD TRUMP stands before a joint session of America’s Congress on March 4th, no one knows what he will say. Policymaking in the world’s biggest economy has become unpredictable, a swirl of executive orders, social-media posts and congressional wrangling. In recent days, for example, Mr Trump has taken to social media to announce a new 10% tariff on China, on top of a similar levy imposed in February, causing Chinese stocks in Hong Kong to fall by over 3% on February 28th. He has also urged Congress to pass a stopgap spending bill to avoid an imminent government shutdown.