I would say a bit more about my position rather than just make the claim that the US has a
long and
proud(?) history of protectionism. The US had and still has protectionist policies. Interestingly, the trade war was not so much protectionist as anti-China. The difference being that the US would rather buy from somewhere else, and if from China then it will be taxed. But protectionism means to protect a countries businesses. There were of course protectionist elements but in my opinion that was not the focus. A famous example of US protectionism was the Japan situation in the 1980s where Reagan forced Japan to limit their output to the US market.
Speaking of Japan, it, from 1930 until about 1970, was a great example of protectionism. No foreign companies were allowed to operate in Japan until 1960, and even then it was only in uninmportant low-margin industries. Imports were completely controlled by the Japanese government, which imported _everything_ based on what they thought was needed: automobiles are something that were almost never imported, for example. China today is less protectionist than Japan at it's peak but still many factors more protectionist than the US. For example, one cannot directly open a foreign business in China. They must work with a domestic company that takes half their profits.
All this isn't to say that the US isn't protectionist, or that protectionism is even bad. But your claim that "The U.S. has a long, proud history of protectionism" really has no qualifying element, and in fact all the qualifiers seem to go in the opposite direct that they should.