After the victory, the force returned to Pearl Harbor on 13 June.
Monaghan was sent north to aid in countering the Japanese threat in the
Aleutians. Damaged by collision in the heavy northern fog,
Monaghan repaired at
Dutch Harbor and Pearl Harbor, then escorted a convoy to the west coast en route to the
Mare Island Naval Shipyard at
Vallejo, CA for a repair period.
Monaghan returned to the South Pacific at Nandi,
Fiji, 17 November. In the harbor of
Nouméa she bent her propellers on an underwater obstruction, and had to return to Pearl Harbor on her hastily replaced port screw for permanent repairs, completed 21 February 1943. Once more in the Aleutians,
Monaghan joined TG 16.69 a scouting force built around
cruisers and . On 26 March this group engaged the Japanese in the
Battle of the Komandorski Islands. Although outnumbered, the Americans fired guns and
torpedoes so effectively that the Japanese were driven away. Patrol and occasional shore bombardment missions throughout the Aleutians, along with escort missions, continued through the summer. Highlights were a
radar-directed surface engagement with an unidentified target 20 June, and a chase of a Japanese submarine two days later that resulted with the submarine being driven up on rocks and abandoned. She was later identified as , engaged in evacuating troops from
Kiska. After escort duty to Pearl Harbor and
San Francisco,
Monaghan sailed to
San Pedro, California, to escort three new escort carriers to the
Gilbert Islands operation, for which they sailed from
Espiritu Santo 13 November. The escort carriers launched their planes against shore targets and protected convoys offshore through the invasion of
Tarawa. Returning to the west coast on escort duty,
Monaghan rejoined the escort carriers after extensive exercises out of
San Diego, California, and prepared for the invasion of the
Marshalls, during which she guarded the carriers northwest of
Roi as they flew air support and strikes for the landings there. On 7 February 1944 she entered
Majuro, then escorted to
Kwajalein, where she joined the transport screen for the capture of
Eniwetok. On the night of 21/22 February, she joined in an all-night bombardment on
Parry Island, then spent a month on patrol and escort duty in the Marshalls. On 22 March
Monaghan put to sea in the antisubmarine screen for the fast carriers, bound for strikes on
Palau,
Woleai, and
Yap, returning to Majuro 6 April. The next sortie, 13 April to 4 May, was to cover the
Hollandia landings, and strike at
Satawan,
Truk, and
Ponape. After preparing at Majuro, the force now sailed for the invasion of
Saipan, against which the first strikes were flown 11 June. While the fliers of TF 58 soundly defeated the Japanese in the
Battle of the Philippine Sea,
Monaghan's group patrolled off Saipan guarding against a possible breakthrough by the enemy. They next steamed to Eniwetok to prepare for the assault on
Guam, for which they sailed 14 July,
Monaghan again in the
antisubmarine screen protecting the carriers. Assigned to cover the work of underwater demolition teams off
Agat on the night of 17/18 July,
Monaghan furnished harassing fire until daylight, firing again on the island during the early morning of 19 June. She continued bombardment and screening missions until 25 July when she sailed for Pearl Harbor, and an overhaul at
Puget Sound. == Loss in a typhoon ==