A dozen Mexican states held elections on Sunday, and—ho-hum—the center-right National Action Party, or PAN, appears to have won seven of the races. The Journal reports that voters in the world’s 15th-largest economy were turned off by the ruling party’s failure to cut debt and tackle crime, and by a boy-wonder president, Enrique Peña Nieto, whom they now regard as more boy than wonder.

I mention this to illustrate that Mexico is a functioning democracy whose voters tend to favor pro-business conservatives, not a North American...