A common theme in discussing the immigration issue is “I love legal immigration, it’s just the illegal kind I’m against.” And there’s no question that political elite’s refusal to enforce the law is the most immediate immigration problem we face. But the “legal is good, illegal is bad” mantra will only get you so far. Even if we were to address the pervasive illegality of today’s immigration flow — by, say, amnestying all the illegal aliens and increasing legal immigration, as the appalling Senate bill calls for — most of the problem would remain. To begin with, the legal and...