U.S. Vice President Mike Pence's hometown of Columbus is as good a place as any to understand how complicated it would be to undo the North American Free Trade Agreement, also known as NAFTA. It's ironic that it's the town in America that, per capita, relies most on foreign trade for its well-being. It took decades for North America to fully implement the rules of NAFTA. What could happen if the deal was suddenly terminated? W5's Lloyd Robertson sits down with former prime minister Brian Mulroney to discuss the key factors that could determine the fate of NAFTA.