While many countries are wrestling with retaliatory tarrifs on US stupidity, China is doing a clever thing.
Sure, they slapped a 39% tariff on US goods, but they've also introduced 'export licensing' for a few critical minerals including dysprosium, terbium, tungsten, indium, and yttrium. They've turned off a tap the US didn't realise it relied on.
This is a good analysis from someone who knows the subject.