" Zapata still has his boots on and his horse saddled."
- PresidentEcheverría, 1976
One way to regard Mexican history is as a pendulum that swings back and forth between progressive and conservative, activist and consolidating currents within the PRI. 1 Generally, the oscillation represents more of a readjustment of policies than a contest between two fixed ideological positions, although the political shift between sexenios has occasionally been quite dramatic. After three rightward-shifting decades punctuated by minor adjustments to the left, the pendulum swung dramatically back to progressive reformism in 1970 when Luis Echeverría became president. Cardenista-style populism returned to Mexico under Echeverria, and with it a revival of agrarismo.
The country needed a new injection of populism to ease rural and student unrest. The social peace that Cárdenas had established in the countryside was threatened by rising campesino militancy, and the impressive economic growth that had once characterized the agricultural economy was no longer even keeping pace with population growth. Not only were food imports up, but agroexport production had lost its former dynamism. To make matters worse, the import-substituting industrialization that since World War II had constituted the motor of the country's