Beginning this month, warrant officers retired from active duty in the U.S. Army will be able to join the Tennessee National Guard.The program has been talked about for years, but Tennessee is the first to implement it, Brig. Gen. Warner Ross, Tennessee’s assistant adjutant general-Army, said in a news release. Previously it was allowed only for soldiers deemed indispensable by the secretary of the Army. Now, nearly all retired active duty Army warrant officers are eligible.