Senior White House adviser Kellyane Conway said Wednesday president Trump “discovered” there was no need for his wall to cover the entire U.S.-Mexico border to work, which experts have been saying since 2016 and Trump himself even referenced back in July.

But Conway made it sound like a revelation. She explained some of the president’s reasoning in an interview with CNN: "There are rivers involved, I'm told.”

The president’s sources — a map, presumably — are correct, as the 1,900-mile Rio Grande runs the entire border between Texas and Mexico.