Tyler Cowen links to somebody saying:

Accepting 60,000 children in a population of 317.2 million — less than two hundred-tenths of 1 percent (.02 percent) of our population — would hardly be straining our resources.

But of course this isn’t about “60,000 children,” it is a symbolic test of national will. If America fails it, then the message goes forth that the door is open in for anybody from anywhere in the world to head to Mexico, where trafficking routes into the U.S. are ready and willing to smuggle you into the welcoming hands of the United States federal government.

Central America has a population of 43 million. But what’s next? Perhaps northern South America, where Colombia, Venezuela, Ecuador, Peru, and Bolivia have a population around 130 million. How much can they send? Little Guyana in northeast South America has about 30 percent of its population living in the U.S. already, according to the Guyanese statehood movement.

Another possibility is the rapidly growing population of the Philippines, which will soon pass 100,000,000 in population. The Philippines has been one of the rare countries in the world where the Catholic Church really has kept contraceptives out of the hands of the poor, although it lost an important political battle last spring. (I’m guessing the Church’s power in the Philippines is because Cardinal Sin — yes, that was his real name — backed Mrs. Aquino after Ferdinand Marcos had her husband rubbed out in 1983.)

There are large Filipino populations in California and Nevada (Filipinos in Las Vegas got hammered by the mortgage meltdown in 2008, which helped Senator Reid win re-election in 2010.) They’ve tended to be middle class (i.e., 90th percentile) legal immigrants because a plane ticket from Manila to Los Angeles is expensive and you still need to talk your way past Customs and Immigration.

But the whole world is watching what’s happening at the Mexican border.

Without a firm response, a smuggling route from Manila through Mexico, following the route of the galleon trade of the 16th Century, could develop. Shipping is quite cheap these days, and Filipino peasants could be loaded in shipping containers for off-loading a couple of weeks later at the cartel-infested port of Port of Lázaro Cárdenas in Michoacán on Mexico’s Pacific coast. The Mexican government has plans to quintuple container traffic through this port, which is 400 miles closer by rail or road to Texas than the port of Los Angeles-Long Beach, by 2020.

Whether this precisely will happen is of course unlikely. But something rather like this is hardly improbable.