The second U.S. Navy warship to bear the name Guam was the second of the controversial large cruisers of the Alaska class. Hull number CB-2—the Guam—was launched on 12 November 1943. Built by the New York Shipbuilding Corporation of Camden, New Jersey, the Guam was commissioned on 17 September 1944.
The Guam and her sister ship, the Alaska (CB-1), were the only battlecruiser-type ships ever completed for the U.S. Navy. Armed with nine 12-inch guns, the Alaskas were the result of an inaccurate prewar intelligence estimate that reported the Japanese were constructing extremely fast large cruisers as commerce raiders.
In February 1945, the Guam joined the Pacific Fleet at Pearl Harbor and shortly thereafter received Secretary of the Navy James Forrestal as a distinguished visitor. The following month, the Guam sailed into Ulithi, where she joined the Alaska as part of the powerful Task Force 58, cutting a path toward Kyushu and Shikoku.
The Guam, training her guns against the enemy, earned her first battle stars when kamikaze aircraft attacked the group's carriers. Despite valiant efforts, the aircraft carriers Enterprise (CV-6) and Intrepid (CV-11) sustained damage. The Guam escorted the USS Franklin (CV-13) out of the combat area, an effort that lasted until 22 March 1945. On 27 and 28 March, the Guam bombarded the airfield at Minami Daito; she supported carrier operations off the Nansei Shoto until 11 May.
The Guam returned to the waters off Okinawa following repairs and replenishment and joined Admiral Halsey's Third Fleet, Task Group 38.4, and once again supported carrier operations off Kyushu. On 9 June, the Guam and Alaska took part in a 90-minute bombardment of Okino Daito. After nearly three months in support of operations around Okinawa, the Guam sailed to Leyte Gulf, arriving in San Pedro Bay on 13 June. Arriving at Okinawa on 7 August 1945, the Guam became the flagship of a North China Force that paraded U.S. naval power around the Yellow Sea and then into Korea in September 1945 to ensure a safe occupation of that nation.
In November 1945, the Guam sailed back to the United States. She remained in New Jersey until her decommissioning on 17 February 1947 and was stricken from the Navy Register on 1 June 1960. She was sold to Boston Metals for scrapping the following year.