Canadian business man on CNN said USA should raise tariffs to 400%. China steal intellectual property, copy and flood markets with cheap price products.
China can only "steal" IP where it's not protected. And it isn't "China" in the sense of some malign entity systematically ripping off inventors. Instead it is a vast sub continent with a nascent IP culture that is rapidly improving, to support the domestic economy amongst other things. But there's a lot of companies in a lot of places to enforce against.
The situation there is better than it was and much better than. For example, most of Africa, most of the Middle East and moat of South and Central America.
The big difference is China is both high tech, highly innovative and a big manufacturer. But if you block them out rather than continue to play "whackamole" with copycats, this doesn't solve the problem and instead disuades western counties from protecting their IP there and availing themselves of the expertise and labour available. Tarrifs make this worse, by generating completely independent economies.
Take Boeing for example, one of Trump's faves, although his last attempts to help them hilariously backfired in Airbus's favour. If he tarrifs them out of the Chinese market and vice versa, all this will do is open the door for Comac to become the supplier of choice for flights around China, Russia and India. That's the majority of the world's population.
May take 10-15 years for damage of this nature to become evident, but this will be Trumps legacy if he isn't careful.