The immigration bill might die in the Senate, as we know, because Marco Rubio, a member of the Gang of Eight, signed off on the Gang of Eight's bill and then (after various tea party eruptions) decided that the Gang of Eight's bill was ridiculously soft on border security.

So now Republicans, following Texas Senator Jon Cornyn, are insisting on strict border security measures. But they're not so much strict as they are basically impossible. I understand that there is an extent to which Cornyn is merely representing the views of his constituents, provided you take his constituents to be not all Texans (the vast majority of the Latino ones) but the white conservative ones that are his base. But their demands and expectations aren't reasonable.

I just got wind of this op-ed that ran a while back in the Journal (the Journal?!?) by Edward Alden of the Council on Foreign Relations about the impossibility of total security. He writes:

Does a secure border mean one in which no one is able to cross between the legal entry ports? The most secure border in modern history was probably the Cold War border between East and West Germany. To keep their people from leaving—logistically much easier than keeping others from entering—the East Germans built more than 700 watchtowers, sprinkled more than a million antipersonnel mines, created a deep no-man's zone of barbed wire and electric fencing, and deployed nearly 50 guards per square mile with shoot-to-kill orders. Even so about 1,000 people each year somehow managed to find a way across.

Judging from my email inbox, there are some in the country who would favor a similar approach on the southwest border, but presumably this is not what is meant by the proponents of "border security first."

As he notes, it's a lot easier to keep people from leaving than from coming. I heard on NPR yesterday that the Border Patrol estimates that to meet the terms of Cornyn's amendment, it would have to go up in personnel from the current 20,000 to 60,000. So during sequestration, while national parks and scientific research grants and all kind of things are being cut deeply, we're going to triple the number of border agents? Cornyn's constituents may demand that, but I doubt very much the whole country does.

This means, in other words, that immigration reform that's supported in new polls this week by upwards of 70 percent of the people is being held hostage to the demands of white conservatives from states along the border (and to a lesser extent from everywhere). This is why Rubio is now against his own bill.