Democrat Tim Walz questions Republican Donald Trump's fitness for office at the outset of Tuesday's vice presidential debate, arguing that the former president is too unstable to be trusted at a time of crisis in the Middle East. His Republican opponent for the country's No. 2 office, JD Vance, responds by asserting that Trump had made the world more secure during his term in office. The ongoing crisis in the Middle East, sparked a year ago by the October 7 Hamas terror onslaught in southern Israel, is the debate's first topic, giving the two men a chance to outline their foreign policy credentials.