Sen. Joni Ernst, the Iowa Republican who is the Senate’s only female veteran, has retired from the Iowa National Guard as a lieutenant colonel, ending a 23-year stint in uniform. Ernst’s decision leaves only one female reservist in Congress, Democratic Rep. Tulsi Gabbard of Hawaii, who, like Ernst, is a combat veteran. “The decision to hang up my uniform after more than two decades in the military is not one I have made lightly and has been incredibly difficult. However, this decision provides me with a greater opportunity to continue meeting with, hearing from and serving Iowans in my capacity as a United States Senator, as well as spending more time with my family,” Ernst said in a statement.