USS Idaho (BB-42): The “Lucky” Battleship of the New Mexico Class

In the annals of U.S. naval history, every ship carries its own tale of courage, circumstance, and survival. Among the storied battleships of World War II, the USS Idaho (BB-42)—a member of the New Mexico-class—stands out not only for her service but also for a twist of fate that spared her from destruction at Pearl Harbor. By not being present during the infamous attack of December 7, 1941, Idaho avoided devastation but also missed out on the extensive modernization that many of her sister battleships underwent. This unusual combination of fortune and oversight shaped her wartime career in ways that highlight the challenges and transformations of the U.S. Navy during the conflict.

The New Mexico Class: A Step Toward the Modern Fleet

The New Mexico-class battleships—comprised of USS New Mexico (BB-40), USS Mississippi (BB-41), and USS Idaho (BB-42)—represented a key evolutionary step in American battleship design. Commissioned between 1918 and 1921, they were improvements over the preceding Pennsylvania and Nevada classes, featuring:

Main Armament: Twelve 14-inch/50 caliber guns mounted in four triple turrets.

Secondary Armament: Sixteen 5-inch/51 caliber guns (later replaced or supplemented with dual-purpose weapons).

Armor Protection: A belt up to 13.5 inches thick, making them formidable for their era.

Propulsion: Steam turbines enabling a top speed of around 21 knots.

The class was notable for pioneering the use of the “clipper bow” and experimenting with turbo-electric drive in one ship (New Mexico). By the 1930s, all three ships underwent modernization, receiving updated fire control systems, improved armor, and anti-aircraft weapons.

USS Idaho: Early Service

Commissioned on March 24, 1919, USS Idaho joined the U.S. Fleet just after World War I ended. Like her sisters, she spent the interwar years conducting training, goodwill tours, and modernization refits. Idaho’s prewar service saw her deployed to both the Atlantic and Pacific, with upgrades that included tripod masts, aircraft catapults, and enhanced gunnery systems.

By the late 1930s, Idaho was considered a reliable but aging vessel, still powerful enough to hold her own in fleet exercises but clearly overshadowed by newer fast battleships like the North Carolina and South Dakota classes.

December 7, 1941: Fortune at Pearl Harbor

When Japanese aircraft struck Pearl Harbor on December 7, 1941, the U.S. battleship force suffered catastrophic losses. USS Arizona was destroyed, USS Oklahoma capsized, and many others—including West Virginia, California, and Nevada—were badly damaged.

But USS Idaho was not in port that morning. She was operating elsewhere in the Pacific, sparing her from destruction. For her crew, it was an incredible stroke of luck. For the ship, however, it was a mixed blessing.

Because the badly damaged battleships required massive reconstruction, they were given extensive modernizations when repaired—new bridges, radar, completely rebuilt superstructures, and heavy anti-aircraft batteries. These “reborn” ships, like West Virginia and California, emerged looking almost unrecognizable from their prewar selves. Idaho, untouched by the attack, did not receive such a complete overhaul. While still upgraded throughout the war, she retained much of her original silhouette and older systems, making her appear outdated compared to her reconstructed sisters.

Wartime Service

Despite being less extensively modernized, USS Idaho remained a vital part of the U.S. Navy’s “old battleship” force. These ships, though slower than the new fast battleships, played critical roles in shore bombardments and amphibious invasions.

Aleutian Campaign (1943)

Idaho’s first major action of World War II came in the northern Pacific, bombarding Japanese positions in the Aleutian Islands, including the recapture of Attu and Kiska. Here, her heavy guns were invaluable in softening enemy defenses in harsh, fog-shrouded waters.

Pacific Island Hopping (1944–1945)

Idaho later joined U.S. forces in the central Pacific, supporting invasions with her massive 14-inch guns. She pounded enemy fortifications in:

Kwajalein and Eniwetok (Marshall Islands, 1944)

Saipan and Tinian (Marianas, 1944)

Leyte (Philippines, 1944)

Iwo Jima and Okinawa (1945)

Idaho’s greatest contributions came in the climactic battles of Iwo Jima and Okinawa. Off Iwo Jima, she delivered sustained bombardments that cleared paths for U.S. Marines. At Okinawa, she braved relentless kamikaze attacks, providing fire support while dodging suicide planes and heavy Japanese artillery.

Idaho survived several close calls, including bomb and kamikaze strikes that damaged but did not cripple her. Her resilience earned her a reputation as a reliable, hard-hitting support ship.

The Contrast with Pearl Harbor Veterans

By 1945, the difference between Idaho and her rebuilt Pearl Harbor sisters was stark. Ships like USS West Virginia and USS Tennessee had towering new superstructures, cutting-edge radar, and formidable anti-aircraft batteries that made them look almost like brand-new battleships.

Idaho, by contrast, retained her older cage mast and original appearance, albeit with radar and more AA weapons bolted on. While she could still deliver devastating gunfire, her dated systems and slower pace limited her to supporting roles rather than fleet actions with carriers and fast battleships.

In many ways, Idaho was a symbol of the Navy’s transitional fleet—a ship that served loyally, but never received the “second life” given to her sisters.

Postwar Fate

After Japan’s surrender, USS Idaho participated in occupation duties before returning to the United States. With the war won and newer battleships dominating the fleet, Idaho was quickly retired. She was decommissioned on July 3, 1946, and struck from the Navy list in 1947.

Her final fate was scrapping in 1947, ending nearly three decades of service.

Legacy of USS Idaho

USS Idaho is remembered today as the “lucky battleship”—spared from Pearl Harbor’s destruction, yet ironically deprived of the modernization that extended the service life of her sisters.

Her career illustrates the unpredictable fortunes of war:

Fortunate to survive untouched on December 7, 1941.

Unfortunate to remain less modernized compared to other Pearl Harbor survivors.

Proud to have fought in some of the most critical campaigns of the Pacific War.

In total, Idaho earned seven battle stars for her World War II service.

Though overshadowed by larger and more famous battleships, she stands as a testament to the grit of the “old battle line” that, despite its limitations, played a crucial role in paving the way for victory in the Pacific.

Conclusion

USS Idaho (BB-42) may not have the fame of USS Arizona or the dramatic rebirth of USS West Virginia, but her story is just as compelling. She was the ship that avoided disaster at Pearl Harbor and went on to fight tirelessly across the Pacific, even if she never received the radical upgrades of her sisters.

In the end, Idaho’s legacy is one of perseverance: a veteran of both the interwar Navy and the Pacific War, a ship whose survival was shaped by luck, circumstance, and the determination of her crew.

Her guns may have fallen silent in 1946, but the memory of her service lives on as part of the proud lineage of America’s battleship fleet.