The Tuscon Sector in Arizona is seeing the most migrant crossings across the southern border as droves of people cross into the U.S. and surrender to authorities. Cochise County Sheriff Mark Dannels says the border wall is "only one component" of border security, emphasizing the need for more support. Correspondent Ali Bradley joins "NewsNation Now" with a look at the border crisis from the air as Republican and Democratic lawmakers spar over how to handle the situation.