If Country A exports 20X more to Country B than Country B does to Country A, which side do you think has more to lose in a protective tariff war? Could it be the country that exports substantially more? Hmm.
If China and the U.S. now install similar tariffs, it is not quantum physics to see that a tariff war will hurt China far more than the U.S.
https://www.americanthinker.com/blog/2019/05/the_trade_war_math.html