China’s massive and growing trade surplus is a danger to producers in the rest of the world. The logical response would be for Trump to engineer a unified response in order to compel a change in Chinese behavior. Instead, he has done precisely the opposite. Unwilling to risk the short-term consequences of a trade war with China and lacking any flair or inclination for diplomacy, he is sucking up to Xi and bullying the rest of the world.
As a result, Xi is a successful mercantilist, even though his policies are damaging to Chinese consumers. Trump is a failed one.