I Know Why Trump Suddenly Hit Brazil and Argentina With Tariffs

President Trump suddenly announced new steel and aluminum tariffs on Brazil and Argentina today, which he blamed on the “massive devaluation of their currencies.” Vox’s Jen Kirby calls Trump’s reasoning “confusing,” which is very charitable indeed. Both the real and the peso are freely traded, which means they get weaker or stronger depending on their countries’ respective economic conditions, not because their governments have devalued anything. Both currencies have indeed weakened, but that’s because they’re both in pretty bad economic shape:
So why did Trump announce the tariffs? There’s no telling why Trump does anything, but my guess is that it’s mostly for domestic political consumption. Tariffs have fallen out of the news lately and the China talks appear to be going poorly. So he picked a couple of countries that compete with our farmers and announced tariffs. It makes him look tough and that’s all he really cares about.
This is just a guess, but a pretty good one, I suspect.