 In 1940 Hines, by now a lieutenant colonel, was posted to the 6th Armored Division at Fort Knox, Kentucky where he commanded 2nd Battalion, 68th Armor Regiment, and then advanced to executive officer of the regiment.In 1943, a reorganization of armored divisions led to an excess of lieutenant colonels, and Hines was assigned to the training and operations staff section (G-3) of Army Ground Forces in Washington, D.C.

Hines received promotion to colonel while with Army Ground Forces, and in September 1944 he was assigned to the staff of the Third United States Army, then fighting in France.In October, he was assigned to command of Combat Command A, 6th Armored Division.