The immigration issue is changing the fate of political parties across the Western world. And young and fresh as he is, on immigration, Rubio is the candidate of the recent past. Someone else is the future.

That someone might be Ted Cruz. Now, Cruz’s immigration attack on Rubio has been met forcefully by the Rubio campaign so far. But Cruz can rely on talk-radio stalwarts like Laura Ingraham, Michael Savage, and others to hammer Rubio on the issue constantly. This is bad for party mandarins. Cruz is loathed by his colleagues in the Senate. His persona electrifies his supporters and his detractors. To the establishment, Cruz looks like Barry Goldwater 2.0 — an uncontrollable right-winger, destined to be blown out.

So you see the near future playing out in the stress nightmares of the Republican establishment. Rubio eliminates Bush on age, polish, and the value of a last name. Cruz eliminates Rubio based on the Florida senator’s support of amnesty. And suddenly, the deepest field in recent history has collapsed into Trump, Carson, Cruz, and some also-rans.

The GOP may get lucky. The race they want, where plausible candidates test each other over several primary contests, across several regions of the nation, may come to pass. Carson and Trump may self-destruct or annihilate each other. But, until something like that happens, leading GOP minds will live in fear of a Trump vs. Cruz battle. And they are right to fear it.