It was just a matter of time before one of the keen-eyed Republican candidates for president spotted the menace that looms over this country, threatening our national security with blasts of Arctic air and proof that socialized medicine works: Canada.

READ: Chris Hedges: The Great Unraveling

Asked on “Meet the Press” whether the United States should consider building a wall to secure its northern border, Wisconsin Gov. Scott Walker said that was “a legitimate issue for us to look at.”

No, it’s not. It’s a laugh-out-loud ridiculous idea. What’s he going to do about the Great Lakes, mine the shoreline? Station heavy artillery at Niagara Falls in case some crafty terrorist tries to come over in a barrel?

But Walker’s folly was only the second-craziest notion on immigration that we heard from a flailing GOP hopeful over the weekend. New Jersey Gov. Chris Christie said that as president he would have the chairman of FedEx “show these people” at Immigration and Customs Enforcement how to track visitors the way his company tracks parcels.

“You go online and at any moment, FedEx can tell you where that package is,” Christie said Saturday at a New Hampshire town hall meeting. “Yet we let people come into this country with visas, and the minute they come in, we lose track of them. … We need to have a system that tracks you from the moment you come in and then when your time is up.”

Just a wild guess, but the reason why visiting foreigners are more elusive than packages might be that human beings are animate, have free will and are not stamped with identifying bar codes. Not yet, at least.

Christie did say one thing that made sense: The argument that Jeb Bush and other candidates are having about the term “anchor babies” is unfortunate because it “makes us sound like we’re anti-immigrant.” You bet it does.

It’s hard to recall that not so long ago, the question about immigration reform was whether the 11 million undocumented men, women and children already in the country should be offered a path to citizenship or merely a way to attain legal status. Now, as far as the GOP field is concerned, it’s whether they can and should be rounded up and deported.

Remarkably, several of the tough-talking candidates are the sons of immigrants — and one of them, Sen. Ted Cruz of Texas, was born in Canada. (Could that be why Walker so pines for a wall? To send Cruz back over it?) But listen to Louisiana Gov. Bobby Jindal, whose parents came here from India and whose given first name is Piyush:

“I think we need to insist that folks who come here, come here legally, learn English [and] adopt our values,” Jindal said on ABC’s “This Week.” “And the reason this is so important: Immigration without integration is not immigration; it’s invasion.”

That’s a long way from “Give me your tired, your poor, your huddled masses yearning to breathe free.” But then again, nativism has long been a powerful force in American political life. Millions of immigrants steamed past the Statue of Liberty, bearing Emma Lazarus’ stirring words, in the early years of the 20th century. But by 1925, the processing center at nearby Ellis Island had largely been converted into a facility for detaining and deporting “undesirables.”

The catalyst for the current eruption of anti-foreigner bombast is, of course, Republican front-runner Donald Trump. His rhetoric blaming undocumented Mexicans for a crime wave and insisting — without a shred of evidence — that the Mexican government is deliberately sending miscreants across the border has struck a nerve. What Trump says about immigration is nonsense and his proposed remedies are infeasible. Yet GOP voters are eating it up.

Among Trump’s rivals, only Bush is forcefully pushing back. “He wants everyone deported, which would tear family lives asunder,” Bush said Sunday. “It’s not conservative and it’s not realistic and it does not embrace American values.”

But as long as other candidates are competing to sound tougher-than-thou, as long as the conversation is about how high to build new walls and blame is ascribed to immigrants for not assimilating quickly enough, the GOP is digging itself a hole that will be hard to escape.

In his last election, President Obama won 73 percent of the Asian-American vote and 71 percent of the Hispanic vote. If the message Republicans send to these groups sounds like “we don’t want any more of your kind,” the Democratic nominee, whoever it is, will have a hard time losing.

Eugene Robinson’s email address is [email protected].

© 2015, Washington Post Writers Group

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