During the Cold War years (1947-1991), the West was caught up in an arms race with the Soviet Union that included nuclear-powered attack submarines. In the 1970s, a new class was ordered by the United States for the role, this to become the powerful Ohio-class group. While some 24 of the class were originally planned, just eighteen were completed with six cancelled. Among the group that survived yearly budget reviews was USS Michigan (SSGN-727).
Ordered on February 28th, 1975 (as USS Michigan (SSBN-727), a ballistic missile submarine), the boat was constructed by General Dynamics Electric Boat and saw her keel laid down on April 4th, 1977. She was launched to sea on April 26th, 1980 and saw formal commissioning on September 11th, 1982. Based out of Naval Base Kitsap in Bangor, Washington, the boat retains an active presence in the American submarine fleet today (2017). She fights under the motto of "Tuebor" - ("I Will Defend").
As built, the boat displaces 16,765 tons when surfaced and 18,750 tons when submerged. She features a length of 560 feet, a beam of 42 feet and a draught down to 38 feet. Power is from a single S8G PWR series nuclear reactor toed to 2 x geared turbines driving 60,000 horsepower to a single shaft. An auxiliary motor provides 325 horsepower when used. Speeds reach more than 25 knots and the boat can head down to depths of 800 feet. Onboard are 140 enlisted personnel with up to 15 officer-level service members. Armament consists of 4 x 21" (533mm) torpedo tubes and the vessel is also cleared to fire the BGM-109 "Tomahawk" cruise missile (154 total can be carried).
USS Michigan (in her SSBN guise) was converted in 2007 to become SSGN (guided missile submarine) while she retained the same designating hull number. Prior to this work the boat had completed dozens of standard patrols under the sea to maintain American interests abroad. Her first SSGN deployment was completed in December of 2009. In June of 2010, she was sent to South Korean waters in response to Chinese missile testing in the region. In April of 2017, she was, once again, located in South Korean waters in response to North Korean missile testing (where she remains as of this writing - 2017). She joins the USS Carl Vinson deterrent force sent to the region.