President Donald Trump's announcement late last week that the U.S. would impose tariffs on all Mexican goods starting on 10 June to "address the emergency at the southern border" was disruptive, but not necessarily surprising. After all, the President shut down the government earlier this year over the same issue and has also threatened to circumvent congressional authority to build a wall on the southern border to stem the flow of migrants; moreover, illegal immigration continuously polls as one of the highest concerns among Republican voters.
With all of that in mind, what might be