Is Mexico the goat we sacrifice to our dread of worse ahead? When I hear Congress about the threat of the Mexican border to our sovereignty, our justice, our well-being, I wonder what has created this anger toward the least among us. None of the facts of immigration suggests there has been any change in the helter-skelter of coming to America for the last three centuries. What explains these elected defenders of freedom proposing a wall as if Arizona were King Kong’s Skull Island, or a round-up of our laborers as if they were the Japanese of FDR’s California?

One explanation for this hysteria is a fear of the 21st century’s challenges. We turn away from the news that our energy supply is in the hands of Tehran’s mullahs, from the fact that the climate is a melting ice cube, and we turn for comfort to the theater of our leadership braining Mexicans one more time as if Washington had just discovered that the New World is heavily populated and hungry.

We have been here before. A century ago, with another pious ideologue in the White House, the Congress and the newspapers used Mexico twice in two years to work out their anxieties about the genuine werewolves then mobilizing in Central Europe.

The first panic attack was the spring of 1914, when a U.S. Navy admiral demanded that the commandant of Tampico apologize for a slight to our sailors. Within weeks, Woodrow Wilson, advocating Mexican regime change immediately, demanded Congress give him war powers and dispatched a squadron to seize the quays at Vera Cruz. At each new hiccup of chauvinism, the newspaper headlines celebrated Wilson and Congress as the Spartans at Thermopylae. The melodrama continued when 3,000 Marines stormed Vera Cruz, and Congress competed for the glamor of instant victory by heaving dozens of Medals of Honor upon the chagrined officers.

Wilson grabbed back the spotlight by ordering an occupation of Vera Cruz until one dictator replaced another and he could withdraw the troops at Thanksgiving. By then, with Europe digging trenches and mass graves, no one thought to mock Wilson’s and Congress’s pantomime of patriotism.

Vera Cruz worked so well that Wilson and Congress knew their punch lines when the Hollywood celebrity Pancho Villa ineptly raided New Mexico and provided an excuse to invade Mexico again in the spring of 1916. It was an election year, and Wilson was getting thrashed by The Republicans for his declaration that he was “too proud to fight” in Europe. Wilson called upon the same general, Fighting Fred Funston, whom he’d used at Vera Cruz to chase Villa’s bandits; and the weary Funston tapped the horse-happy General John Pershing to head the so-called Punitive Expedition.

Headlines celebrated the romance of “flying” cavalry columns and 15-mile-an-hour truck convoys and the first-ever Army airplanes crisscrossing deserts and mountains in pursuit of a quotable though vanished villain. Within months, Wilson and the Mexican dictator Carranza had mishandled the gunplay enough so that the newspapers convinced the American public that Mexico was about to invade America.

No one laughed; no one even doubted the sanity of deploying 100,000 National Guard troops to camp in a wilderness. Meantime, Wilson strutted in “National Preparedness” parades in Washington and New York and campaigned as just enough of a warlord to win the presidency by a handful of late votes from threatened California.

Four generations on, it is easy to see that Wilson and his Congress cared no more about Villa than they did about Vera Cruz. What fueled their panic was their fear of the forces of nationalism – forces that were about to eviscerate Europe and Asia and Africa. Then again, Woodrow Wilson and his Congress are acceptable now as cynical men who knew how to kick a pup rather than hunt a predator.

Today, Wilson’s cunning seems unattainable. When I listen closely to the breast thumping sermons of George Bush and his Congress as they denounce and defame Mexico, I fret that perhaps they really believe this guff that an army of Mexicans is invading America, that Mexican want is ruining the neighborhood, that a proto-jihadist named Pancho Villa rides again, if only in the fevers of the scared witless.

Mr. Batchelor is host of “The John Batchelor Show” on the ABC radio network. The show airs in New York on 770 AM from 10 p.m. to 1 a.m.