In May 2017, Merkel launched a subtle jab at Trump, saying at a campaign event: "The times in which we could fully rely on others are partly over. I have experienced this in the last few days. We Europeans really have to take our destiny into our own hands."
Trump then hit back on Twitter a few days later, writing, "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."
But economists say the trade deficit is not necessarily a bad thing, because while Americans spend more on German goods, Germans tend to save at a higher rate, meaning that much of those savings end up being invested in the United States economy.
Source: Washington Post, Business Insider, Twitter