Acquiring Private Land Is Slowing Trump's Border Wall

Acting Homeland Security Secretary Chad Wolf visited a construction site in the Rio Grande Valley of Texas on a windswept day last month and repeated a Trump administration pledge.

"We are on track to build 450 to 500 miles of new wall by the end of 2020," he told reporters. Behind him, steel panels atop a concrete levee wall, 30 feet in all, are rising from the sugar cane fields and bird sanctuaries of the valley — which is really a river delta. They are the first section of new...