Former Rep. Beto O'Rourke said Thursday that if he were president he would "absolutely" take down the border wall in El Paso, Texas. O'Rourke told MSNBC host Chris Hayes that "walls don't save lives." "Here's what we know, after the Secure Fence Act, we have built 600 miles of wall and fencing on a 2,000-mile border. What that has done is not in any demonstrable way made us safer," O'Rourke said. "It has cost us tens of billions of dollars to build and to maintain and it has pushed migrants and asylum seekers and refugees to the most inhospitable, the most hostile stretches of the U.S-Mexico border." "It's perverse, the response that we have to legitimate concerns and problems, international terrorism, which was orchestrated in Afghanistan by al Qaeda, carried out by people from Saudi Arabia, we punish people from Mexico at the U.S.-Mexico border, deport in one year alone 400,000 Mexican nationals from this country from a response to 9/11," O'Rourke said. "We wall off 600 miles of the U.S.-Mexico border. Precisely zero terrorists or terrorist organizations have ever used the border to attack a single American."