Donald Trump hasn’t been talking about the rising stock market lately, and no wonder. Stocks have given up their earlier gains since the President unveiled his protectionist trade agenda, and the Dow Jones Industrial Average fell another 1.9% on Monday. Tech stocks took a particular beating as Nasdaq fell 2.74%, but the main policy concern is the new uncertainty from rising trade tension.

China slapped punitive tariffs on 128 categories of American goods on Monday in retaliation for the Trump Administration’s national-security…