I gotcher moderate Republican for ya right heah

HANNITY: The only two issues I ever hear conservatives critical towards you about, immigration, and the refugee issue, which you and I discussed the last time you were on the program. I want to give you an opportunity to expand on this. Should people who do not respect our law and sovereignty, why should they have a path towards citizenship?

KASICH: I'm for legalization, Sean. I'm not for giving anybody a path to citizenship here.

HANNITY: No citizenship?

KASICH: No, I don't believe in that. But I do believe if they've been law abiding in this country, they can get to legalization. They have to pay a fine and everything else.

But the wall has to go up, Sean.

Look, Reagan was for letting these folks stay in 1986. Where did they fall down? They didn't enforce the law. We need to finish the wall. And if you come over for any reason, you're going back. I don't want to argue or discuss it with them. You got to go back. But for the ones that are here, I think they can be given a path to legalization. If they broke the law, that's a whole other story.

HANNITY: A path to legalization but no citizenship. Just to be clear --

KASICH: No, I don't believe we should --

HANNITY: OK.

KASICH: Correct. I believe we should go to legalization, but not citizenship. I don't believe in that path.

human beings have built a 2,000-mile-long frontier wall exactly one time. Once. And it was accomplished only through a centuries-long building campaign that necessitated the forced labor of millions of Chinese peasants.

The challenge of Trump’s border wall is not technical, but logistical. The leap in complexity between “building a wall” and “building a 2,000-mile-long continuous border wall in the desert” is about equal to the gap between “killing a guy” and “waging a protracted land war.” Trump’s border wall, if built as he has described it, would be one of the largest civil works projects in the history of the country and would face an array of challenges not found when constructing 95-story skyscrapers.[...]

If we assume a border wall length of 1,954 miles (there are 600 or so miles of existing border barrier, but much of this would not qualify for Trump’s wall), then we can make some estimates as to the volume of concrete needed for the project:

Foundation: 6 feet deep, 18 inch radius = 42.4 cubic feet
Column: 4 square feet area by 30 feet tall = 120 cubic feet
Wall panels: 25 feet tall by 10 feet long by 8 inches thick = 166.7 cubic feet
Total concrete per 10-foot segment = 329.1 cubic feet
1,954 miles = 10,300,00 feet = 1,030,000 segments (10-feet long each)
1,030,000 segments * 329.1 cubic feet per segment = 339,000,000 cubic feet = 12,555,000 cubic yards. (The cubic yard is the standard unit of measure of concrete volume in the United States.)
Twelve million, six hundred thousand cubic yards. In other words, this wall would contain over three times the amount of concrete used to build the Hoover Dam — a project that, unlike Trump’s wall, has qualitative, verifiable economic benefits.

Such a wall would be greater in volume than all six pyramids of the Giza Necropolis — and it is unlikely that a concrete slab in the town of Dead Dog Valley, Texas would inspire the same timeless sense of wonder.

That quantity of concrete could pave a one-lane road from New York to Los Angeles, going the long way around the Earth, which would probably be just as useful.

Concrete, of course, requires reinforcing steel (or rebar). A reasonable estimate for the amount of rebar would be about 3 percent of the total wall size, resulting in a steel volume of 10,190,000 cubic feet, or about 5 billion pounds. We could melt down 4 of our Nimitz-class aircraft carriers and would probably be a few cruisers short of having enough steel.

But the challenge is far greater than simply collecting the necessary raw materials. All of these hundreds of miles of wall would need to be cast in concrete facilities, probably project-specific ones that have been custom built near the border. Then, the pre-cast wall pieces would need to be shipped by truck through the inhospitable, often roadless desert.

The men and women doing the work of actually installing the wall would have to be provided with food, water, shelter, lavatory facilities, safety equipment, transportation, and medical care, and would sometimes be miles away from a population center of any size. Sure, some people would be willing to to do the work, but at what price? Would Trump hire Mexicans?

This analysis also ignores the less sexy aspects of large-scale engineering projects: surveying, land acquisition, environmental review, geological studies, maintenance, excavating for foundations, and so on. Theoretical President Trump may be able to executive-order his way through the laser grid of lawsuits that normally impede this kind of work, but he can’t ignore the physical realities of construction.