A Southern Pacific special pulled into the San Antonio train station on June 15, 1917, and more than 400 Chinese nationals poured onto the platform to take a peek at their new home.

The American Punitive Expedition failed to find Pancho Villa, but the footsore soldiers did not come back from Mexico empty-handed. Although the March 1916 attack on Columbus, New Mexico went unavenged, Gen. John J. Pershing had nearly 3,000 refugees to show for his time and trouble.

To stem the tide of Oriental immig...