How Trump will build his Mexican border wall

The issue

President Trump unveiled today an executive action to get to work on his wall on our border with Mexico.

The facts

Trump wants a 1,000 mile wall, constructed of concrete and steel, between 35-60 feet high. The other 1,000 miles of the border won't need a wall because of natural obstacles, including mountains and deserts. Trump says the wall will cost $8-12 billion, but the MIT Technology Review took a more critical look and predicts between $27-40 billion.

There's already about 650 miles of fencing on the border, courtesy of a 2006 law signed by George W. Bush. The effort focused on high traffic areas for border crossings of illegal immigrants and drugs, and cost a little less than $3 billion. Previous attempts to build a bigger wall or install more high fencing stalled in Congress.

What's next: Trump plans to have Congress pay for the first part of the wall using that 2006 law. He claims he'll get Mexico to pay us back using NAFTA re-negotiations and by potentially freezing remittances from Mexican nationals in the United States. Mexico says that won't happen.