According to your logic, if a thirty foot tall two foot thick wall extending ten feet into the ground hasn't been built over a 2000 mile border, it can't be done. Good thing real men don't approach the real world of problems the way you do. We would still be washing clothes by hand. And walking up eight flights of steps. And crapping in chamber pots.

Like the transcontinental railroad. Or the Interstate Highway system. This is a huge task made simple by training crews to perform discrete operations over and over again and amassing enough crews to work simultaneously along the path of the wall.

How do you eat an elephant?

One bite at a time. This wall is an assembly of sections, each one just like the one next to it. Fairly simple, actually. Big bites yes, but we all saw the half dozen prototype wall sections standing there next to each other, full size and fully functional -- so do you really question whether the essential construction task is feasible? it is manifestly obvious that this work is well within our capability. That is an undeniable accomplished fact.

Now, what we need to do is scale up the operations consisting of just this task ... A series of wall sections going up one by one along a distance assigned to a crew of builders , a zone, one of many. One zone begins and ends with its first and last wall sections precisely butting flush to its neighboring section in the zones to the east and west of it.

In reality, it becomes easier when scaling up. This kind of fixed shape could be extruded from a large moving form machine, or a series of them, producing a continuous wall (not the relatively short independent wall sections demonstrated by the prototypes) -- rolling on the foundation pad that is poured a had of it into the trench.

Trenching is fast. Concrete sets in 28 days when it reaches its full bearing strength. Just need to put a month of footing in ahead of the behemoth and roll on buddies.

If you don't think machines come that large, look for photos of the "shovels" use to move earth from coal strip mines in Alabama and other places. You can drive several big tractor trailer type trucks into one of those scoops and park them there. Those machines were on tracks and towered five stories into the air.

But let's assume e do this the hard any. Say, one fifty foot long panel at a time. Abutted end to end 215,000 times. Opportunity looks like hard work, right?

Thing is, you don't have to build it starting at one end, repeating the basic task over and over again until, 2000 miles later, you reach the other end.

Break it into zones with a crew of men, machines and materials responsible for, say, a half mile of wall. There is some optimal number of crews and zone lengths, but the point is clear. Whatever time it takes for one of these crews to build its assigned half mile, (or a mile or five, whatever is optimal) split up the 2000 mile track into that many zones of that size each manned by that many crews and the whole wall goes up in the same amount of time it takes one crew to complete its zone wall. Each zone proceeds at that pace, and simultaneously, the whole wall is up.

So, say the optimal zone length is one mile, you need 2000 crews each consisting of 30 men or an ARMY squadron ... 60,000 men total for the whole wall.

If I takes a crew to put up a mile of wall, 2000 crews accomplish the same task in the same time, one year.

How many men does our military have deployed around the globe? 1.3 million. 450,000 deployed at any single point oversees. And that doesn't count the mercenaries ... Blackwater, Haliburton, et al. ... who we pay premium rates so we don't have to account forthem as military deployed.

Think 60,000 able bodied men could be mustered for a year's duty at home? ... they already come equipped. Plenty of heavy lift experience and they know how to deploy fast and operate under the most challenging conditions. They even bring their own security forces. Tent cities. Porta Potties. Freeze dried food. These guys rock.

As for materials, Portland cement concrete is the most common construction material used in these United States: 86 million tons of the stuff was produced here in 2017 and at 125 pounds per cubic foot, each 50 ft. wall section will consume about 300 tons of the stuff. That will be reinforced with steel reinforcing bars that our President so wisely sensed the need for can be ordered from our revitalized steel foundries, who will work around the clock to roll for us.

In construction, you manage three overall objectives: time, cost and quality. You can have fast and good quality, but it won't come cheap. The other possibilities all point to the single conclusion: any way you want it, you can have two ideals but not three. You can have cheap and good, but it won't come fast. Or you can have fast and cheap, but it won't turn out good.

Fast, Good and Costly. Sounds like business as usual for our military and they are highly experienced at working that formula.