Global trades depends upon a global economy. Which is in the early stages of ceasing to function as it has the past few decades. China has been unwilling to play by the established international trade rules. This was by and large a minor disruption to the global economy. As China's economy has grown and China actions becoming aggressive, this disruption becomes a serious concern.
While I don't agree with Trump's particular strategy and execution, it was far past time the US played hardball with China. The idea was we could simply make deals with them and ignore their blatant disregard for the rules and China would 'grow up' and learn that playing ball was the best deal for all involved. They didn't.
Add to that China is militarizing the South Sea, has a stated goal to build a US beating military by 2035 (and many in China think it could already beat the US in a war), and we have a pretty classic recipe for a war. China will control the South Seas and they will end the free passage of trade that currently exists in that very important region of world trade.
The US needs to accept global free trade is not going to happen with the present players at the table. The US needs to start uncoupling itself from China. And needs to reconfigure the economy to work with Europe and Americas. The US now allows the Chinese (through Chinese corporations) to own important pieces of infrastructure such as ports of entry in the US. That is insane. US needs to end that now. Even it if means nationalizing. Another focus should be on Mexico and then central/South America. The US should throw considerable resources into stabilizing these region. It starts with ending the so called war against drugs. And be willing to use military options where we have partners on the ground. Focus on assisting in building infrastructure. The US has done little to take advantage of Central America and the entire continent of South America. We should emulate the Chinese's belt and road initiative in South America. The US should also throw considerable investment into automated manufacturing Stateside. These would have the double benefit of becoming more independent and cutting the Chinese legs out from underneath them.
We can fight world war 3 after giving the Chinese the money to build a custom built military to beat ours. Or we can stop funding their war machine and force them to come to heel now.