USS Decatur (DDG-73) is an Arleigh Burke-class destroyer in the United States Navy. She is named for the former naval officer Stephen Decatur, Jr. This ship is the 22nd destroyer of her class. USS Decatur was the 13th ship of this class to be built at Bath Iron Works in Bath, Maine, and construction began on 11 January 1996. She was launched on 10 November 1996 and was christened on 8 November 1996. On 29 August 1998 she was commissioned at the Tom McCall Waterfront Park in Portland, Oregon.

The Aegis ballistic missile defense system, also known as Sea-Based Midcourse, is a Missile Defense Agency program under the United States Department of Defense developed to provide missile defense against short and intermediate-range ballistic missiles. The program is part of the United States national missile defense strategy and European NATO missile defense system.