China’s Unprecedented Defiance of US Sanctions Triggers Showdown

China has ordered its companies to ignore US sanctions, an unprecedented act of defiance that threatens to trap a vast banking sector in the crossfire as tension rises between the world’s largest economies.

Beijing has often railed against unilateral sanctions and pronounced them illegitimate, but it has also quietly allowed its largest companies to comply with them, in order to avoid blowback on its own economy and to preserve access to the US financial system.

Saturday’s announcement — coming before a long-awaited meeting later this month between President Donald Trump and his counterpart Xi Jinping — signals a far more ...