Mike Waltz, Ret. Adm. Michael Mullen

Mike Waltz, the U.S. ambassador to the United Nations, told ABC News on Sunday that President Donald Trump wants Iranian leaders who will not threaten "the United States or allies in the region" when asked about the president's recent comments on choosing the country's next head of state. Retired Adm. Mike Mullen, former chair of the Joint Chiefs of Staff, said Sunday that he has doubts that the U.S. can successfully pull off regime change in Iran. Panel: "New Yorker" staff writer Susan Glasser, "Atlantic" staff writer Anne Applebaum, and ABC News chief White House correspondent Mary Bruce.