 After graduating from the War College in 2009, Kirklin returned to Fort Hood, and assumed command of the 4th Sustainment Brigade on 14 July 2009.He deployed as the 4th Sustainment Brigade to Tallil, Iraq, in support of Operation New Dawn in February 2011.Kirklin redeployed the Brigade from Tallil, Iraq, in December 2011, after serving as the final Sustainment Brigade to close out sustainment and retrograde operations to end Operation New Dawn.