DHS Sec. Mullin is revealing what he sees as America's biggest vulnerability, and it's not coming across the border, it's coming from the air. Mullin says counter-drone defense is his "biggest concern," pointing to how unmanned aircraft are reshaping modern wa

DHS Sec. Mullin is revealing what he sees as America's biggest vulnerability, and it's not coming across the border, it's coming from the air. Mullin says counter-drone defense is his "biggest concern," pointing to how unmanned aircraft are reshaping modern warfare in Russia and Ukraine while warning that Iran is increasingly moving in the same direction. "We're better than most countries, but we're not where we need to be." As adversaries ramp up drone warfare, Mullin says the U.S. needs to close that defense gap. @​WillCainShow ▻