Trump tariffsUS president likely to find levy threat gives little leverage over Xi JinpingU. S. President Donald Trump is set to meet Chinese leader Xi Jinping in Beijing this week, as they look to preserve their trade truce. (Nikkei montage/Source photos by Reuters)SHANGHAI -- When U. S. President Donald Trump talks trade with Chinese counterpart Xi Jinping this week, he is likely to find that tariff threats provide less leverage than they used to, not only due to lost legal battles but also because Chinese companies have spent years diversifying global supply chains.