Thomas Donlan of Barron’s explains why he is no fan of President Trump’s 140-character tirades about trade.

In many tweets, Trump has fixated on having some foreign country pay for something: Mexico should pay for his wall; European countries should pay for the North Atlantic Treaty Organization; China should “solve” the North Korea problem in order to make a trade deal; Canada should not compete to take away customers from U.S. dairy products or U.S. lumber.

When the president returned from his foreign trip a week ago, he reported, “We have a MASSIVE trade deficit with Germany, plus they pay FAR LESS than they should on NATO & military. Very bad for U.S. This will change.”

Ignorance is not bliss. If Trump knew more than the single number for the balance of trade, he would be happier with the trade relationship between the U.S. and Germany.

Our trade deficit—the amount that imports exceed exports—with Germany last year was about $65 billion, or some 13% of the U.S. total 2016 trade deficit. It’s big because Germany is a big country, a highly efficient producer of many high-value goods for export, and because Americans can use their strong dollar to buy cheaply from the euro zone. Germany’s profits have built a country with high wages and strong unions. As a member of the European Union, it doesn’t even control its own trade and monetary policies. The only unfair thing is that they are “massively” good at minding their businesses.

Partly to recycle the dollars they have earned, German companies have done the U.S. the very large favor of investing $255 billion in America over the years, including the construction of car factories by Daimler, Volkswagen, and BMW. All three export vehicles from the U.S. to other markets, which reduces the goods trade imbalance. And if jobs matter, U.S. affiliates of German firms employ more than 670,000 Americans.