Mexico border wall plan : Trump Wall realistic or not             

Mexico border wall plan : Trump Wall realistic or not             

WASHINGTON: (APP) Even as Donald Trump vacillates between toning down his harsh anti-immigrant rhetoric and reaching out to minorities, he remains unshakable on one central campaign promise: building a wall on America's southern border with Mexico.

"We are going to build a great border wall to stop illegal immigration, to stop the gangs and the violence, and to stop the drugs from pouring into our communities," the Republican presidential candidate said as he accepted his party's nomination last month.

It's an idea experts say is as useless as it is unrealistic. Though that has hardly given Trump pause.

"I will build the greatest wall that you have ever seen," he elaborated at a recent rally. "That's a Trump wall, a beautiful wall!"

"And who's going to pay for it?" he asks at his events.

"Mexico!" his energized supporters roared back.

Trump says his success as a construction magnate guarantees he can build such a wall but has provided few details.

The 2,000-mile (3,200-kilometer) US-Mexico border runs from the Atlantic Ocean to the Pacific, crossing arid, sparsely populated territory as well as urban centers thick with inhabitants.

After initially promising to build a new barrier running the entire length of the border, Trump now says only half actually needs to be covered because the physical terrain acts as a natural barrier along the rest.

But if he's clear about the length, what about the height? Trump has variously mentioned 35 feet (10.5 meters), 40 feet, 55 feet and even 90 feet.

"The wall just got 10 feet higher!" he's said when Mexican officials repeated that their country has no intention of paying a dime.

He is just as vague about the cost -- $4 billion, then "six or seven" billion, "probably eight," and "10, maybe 12," before finally settling at "around $10 billion."

However, architects and engineers dismiss that figure as entirely unrealistic given even the minimum predictable costs.