Anchored by Jake Tapper, The Lead airs at 4 p.m. ET on CNN.
What's the U.S. plan on Russia's "all out" invasion? Plus, a look at the strategy for fighting ISIS.
Killeen, Texas (CNN) - With the community reeling from a shooting rampage at Fort Hood, investigators are grappling for answers on why Spc. Ivan Lopez opened fire against fellow soldiers.
Investigators are looking at a possible altercation with a soldier "that immediately preceded the shooting," said Lt. Gen. Mark Milley, the post's commanding general.