US-China trade/tech war escalates with enforcement actions

China detains Japanese businesspeople over rare earth/dual-use export controls, signaling personal legal risks. New tariff bills advance in US Congress, tungsten curbs hit Japan (zero exports since Jan 2026), and China retaliates with anti-dumping duties. AI chip race intensifies with Nvidia share collapse and US legislative proposals to cap China's AI compute. China also curbed exports to Lithuanian laser maker Ekspla, broadening the export control front.