Here's why John Bolton and John Kelly were at each other's throats today
John Kelly addresses the USO of Metropolitan Washington-Baltimore's 35th Annual Awards Dinner, Arlington, Va., March 21, 2017. (U.S. Army National Guard photo by Sgt. 1st Class Jim Greenhill)

CNN's "The Lead" Thursday reported that the intense shouting match between John Bolton and John Kelly, which escalated to the point where observers worried both men might resign, occurred over Secretary of Homeland Security Secretary Kirstjen Nielsen.

According to CNN reporter Kaitlan Collins, Bolton shouted that Nielsen needed to be better at her job, while Kelly defended the embattled Nielsen.