That’s not my impression. I perceive the tariffs as a response to the yawning trade deficit between China and the U.S., as well as China’s state-sponsored IP theft from U.s. companies, currency manipulation, technology transfer requirements for foreign companies, Party cell embedding requirements [0], and various other protectionist policies.
As for evidence of necessity: the U.S.-China trade gap is hundreds of billions of dollars, on top of all that other stuff.
[0] https://www.washingtonpost.com/world/asia_pacific/command-an...