Into Guatemala City's Aurora Airport last week flew Mexico's President Gustavo Díaz Ordaz. To the shattering accompaniment of a low-flying formation of Sabre jets, he proclaimed that Guatemala and Mexico, both home to the Maya Indians who pounded corn meal into tortillas, were "brothers in ancient culture, in blood, in language and in our way of life, even to the corn which is the sustenance of our people."
It was a sentimental, even corny way to begin the first visit by any Mexican President to Central America, but Díaz
Ordaz hoped that it meant the beginning of a new era in...