Today, April 12th, Trump backed down again on his tariff threat to China. All cellphones and computers are now tariff-exempt.

No, Trump is intentionally clouding the issue while American interests find alternatives to China. And Canada for that matter. Moving a car plant from China (or Canada) to a more trade friendly place takes time. And of course it's expected that China (and Canada) will get nasty when the announcements come. So it's important for US interest take steps to move the most valued assets beyond the reaches of China (or Canada).