Benson received a Letter of Commendation, with authorization to wear the Commendation Ribbon, for his role as executive officer and navigator on the USS Nautilus during the Battle of Midway.
 The Nautilus also received the Presidential Unit Citation for this engagement.
 Benson was promoted to lieutenant commander in 1942.

After brief duty on the staff of Submarine Squadron 10, Benson assumed command of the submarine USS Trigger (SS-237) on August 29, 1942.
Edward L. Beach would later credit Benson's leadership during the next four war patrols for restoring the crew's morale.
Ironically, Benson's most far-reaching contribution to the submarine campaign against the Japanese Empire was the failure to sink the aircraft carrier Hiyō during his final war patrol as Trigger's skipper.
 This proved to be the "final straw" for Vice Admiral Charles A. Lockwood, the Commander Submarines Pacfific Fleet (COMSUBPAC), who ordered the magnetic exploders be deactivated on the trouble-plagued Mark 14 torpedo.

For distinguished service in command of the Trigger, Benson was awarded the Navy Cross, a Gold Star in lieu of a second Navy Cross, a Silver Star Medal, and a Gold Star in lieu of a second Silver Star Medal.
 Trigger also received the Presidential Unit Citation.
 He was promoted to commander in 1943.

Relieved of command of the Trigger in July 1943, he was placed in command of the Prospective Submarine Commanding Officer's School at the New London Submarine Base.

From June to October 1944, Benson commanded the submarine USS Razorback (SS-394) and later commanded Submarine Division 43.
Benson led a wolfpack consisting of Razorback, Trepang (SS-412), and Segundo (SS-398) that set sail on November 5, 1944.
 Operating in the Luzon Strait and the South China Sea, a convoy of seven escorted merchant ships was sighted and the three submarines made night attacks, sinking all of the merchant vessels, on December 6.

Benson led another wolfpack consisting of Razorback, Segundo, and Seacat (SS-399) that set out for the East China Sea on February 1, 1945.
Razorback sank four wooden ships in three separate surface gun actions and deposited three Japanese prisoners at Guam.
Segundo attacked Japanese shipping off the Korean coast, sinking a cargo ship on March 11.
Seacat attacked Japanese shipping off the coast of Kyūshū.

For outstanding services while in commanded Submarine Division 43, Benson was awarded the Legion of Merit.
Benson received a Letter of Commendation, with authorization to wear the Commendation Ribbon, for his role as executive officer and navigator on the USS Nautilus during the Battle of Midway.  The Nautilus also received the Presidential Unit Citation for this engagement.  Benson was promoted to lieutenant commander in 1942.
After brief duty on the staff of Submarine Squadron 10, Benson assumed command of the submarine USS Trigger (SS-237) on August 29, 1942. Edward L. Beach would later credit Benson's leadership during the next four war patrols for restoring the crew's morale. Ironically, Benson's most far-reaching contribution to the submarine campaign against the Japanese Empire was the failure to sink the aircraft carrier Hiyō during his final war patrol as Trigger's skipper.  This proved to be the "final straw" for Vice Admiral Charles A. Lockwood, the Commander Submarines Pacfific Fleet (COMSUBPAC), who ordered the magnetic exploders be deactivated on the trouble-plagued Mark 14 torpedo.
For distinguished service in command of the Trigger, Benson was awarded the Navy Cross, a Gold Star in lieu of a second Navy Cross, a Silver Star Medal, and a Gold Star in lieu of a second Silver Star Medal.  Trigger also received the Presidential Unit Citation.  He was promoted to commander in 1943.
Relieved of command of the Trigger in July 1943, he was placed in command of the Prospective Submarine Commanding Officer's School at the New London Submarine Base.
From June to October 1944, Benson commanded the submarine USS Razorback (SS-394) and later commanded Submarine Division 43. Benson led a wolfpack consisting of Razorback, Trepang (SS-412), and Segundo (SS-398) that set sail on November 5, 1944.  Operating in the Luzon Strait and the South China Sea, a convoy of seven escorted merchant ships was sighted and the three submarines made night attacks, sinking all of the merchant vessels, on December 6.
Benson led another wolfpack consisting of Razorback, Segundo, and Seacat (SS-399) that set out for the East China Sea on February 1, 1945. Razorback sank four wooden ships in three separate surface gun actions and deposited three Japanese prisoners at Guam. Segundo attacked Japanese shipping off the Korean coast, sinking a cargo ship on March 11. Seacat attacked Japanese shipping off the coast of Kyūshū.
For outstanding services while in commanded Submarine Division 43, Benson was awarded the Legion of Merit.
Roy S. Benson