The idea behind comprehensive immigration reform is that we ought to combine three separate things. The first and most politically contentious part is granting legal status of some kind to some share of the 11 million to 12 million unauthorized immigrants currently living in the United States. The second and least politically contentious part is welcoming a larger number of skilled professionals, entrepreneurs, scientists, and the like. The third and most underappreciated part is welcoming large numbers of less-skilled workers, whether through a guest-worker program or some other mechanism.

Politically speaking, wrapping these three very different things in the same neat package makes a lot of sense. Comprehensive immigration reform unites high-tech companies looking for cheap software developers; agribusiness companies looking for cheap agricultural laborers; and ordinary voters, many of whom are immigrants themselves, who recoil at the idea of mass deportations that could, among other things, break up families and communities. Think of it as mutual hostage-taking.

No, GoogleAppleFacebook, you can’t hire more brainiacs from Belgium unless we grant legal status to the unauthorized. No, DREAMers who want to stay in America, you don’t have the political muscle to get legal status without also getting the lettuce lobby on board.