Mark L. Feldman and Michael F. Spratt in their book Five Frogs on a Log tell about a family visiting Mexico that found itself in a difficult situation. On Sept. 6, 1960, the Salado River in Sabinas, Mexico, overran its banks. Flood waters filled the main road leading from Sabinas across the border into the U.S. Numerous cars and trucks stalled while attempting to cross the border. However, a tow truck driver observed the mess with happy anticipation. You can guess why. He charged an exorbitant fee to tow waterlogged cars across the border.

Along came this old station wagon, packed with this family from the U.S.--a man, a woman, and three small children. They were obviously tired and eager to return home. The man approached the tow truck driver about a tow across the border. The truck driv…