Summary and Key Points: The USS Idaho (BB-42), a New Mexico-class battleship, was one of three “super-dreadnoughts” built as part of the U.S. Navy's “Standard Type” battleships during World War I. Commissioned in 1919, Idaho was armed with 14-inch guns, torpedoes, and anti-aircraft capabilities.

-Although relatively slow, the Idaho served as a crucial support vessel during World War II, participating in key campaigns such as the Marshall Islands, Saipan, Guam, Iwo Jima, and Okinawa. She earned seven battle stars for her service.

-Notably, the Idaho avoided destruction during the Pearl Harbor attack and later played a role in the occupation of Japan. After witnessing the Japanese surrender, Idaho was decommissioned in 1946 and sold for scrap in 1947, marking an ignominious end to a storied career.

USS Idaho: The Battleship That Played a Crucial Role in WWII

During the late nineteenth and early part of the twentieth centuries, the most desirable warships to have in one’s fleet were glorious battleships. These behemoths were primed for delivering unstoppable firepower upon targets both at sea and on land. At the end of the First World War, one battleship class in particular, the New Mexico-class, would take center stage.

New Mexico-class battleships were the second class of the “standard type” battleships that the Navy procured following the success of the Nevada-class battleship. 

Just What is a “Standard Type” Battleship?

As an aside, the term “standard type,” refers to the standardization of the development of these classes. Indeed, there was a coterie of twelve battleships created which spanned five different classes between 1911 and 1916. All these battle boats were built according to a similar standard. They were considered to be “super-dreadnaughts,” because they were relatively smaller than other battleships that had come before and after them (but don’t let that description fool you. Battleships in general were sea monsters).

According to Joseph Czarnecki writing at NavWeaps, “Each small class incorporated a progressive series of improvements while retaining enough commonality for the individual ships to operate successfully as a homogenous whole in the line of battle.” In modern parlance, we might have described this as a “plug-and-play” model. In fact, we might even say that the turn-of-the-twentieth century “super-dreadnaughts” were more effective at plug-and-play-style ship design than we moderns have been (the Littoral Combat Ship, for example, is meant to be a modular warship that can be reconfigured for specific mission sets).

The New Mexico-class Battleship

Anyway, the New Mexico-class (a.k.a. “Battleship 1915”) was the third such “Standard Type” battleship design the Navy built. The Navy added new features to these boats, such as an extra half inch of deck armor, and the “clipper bow,” the Navy removed some secondary guns on the midship and installed triple turrets of 14-inch .50 caliber guns with individual sleeves. 

Three warships would be part of this legendary battleship class. Among them were the USS New Mexico (BB-40), the USS Mississippi (BB-41), and the USS Idaho (BB-42). That last battleship will be the focus of this piece. 

The USS Idaho

As noted above, the BB-42 was built with multiple 14-inch guns, which were the biggest guns on an American battleship. These boats could deploy torpedoes from its two Mk. 15 21-inch torpedo tubes. Further, they had a robust anti-aircraft capability, consisting of fourteen 5-inch 51 caliber guns and 8.3-inch .50 caliber anti-aircraft guns.

Since the New Mexico-class was part of the battleships developed during America’s involvement in the First World War, multiple features were incorporated into these ships that were meant to respond to the sophisticated naval capabilities of rival nations, notably Germany. They were designed to be more heavily armed and could move faster than the battleships that preceded them. 

The USS Idaho had a crew of around 1,084 people and her nine Babcock & Wilcox boilers that generated energy for the General Electric (GE) turbo-electric engines could take this boat to about twenty-one knots (about twenty-fourmiles per hour). This was a relatively slow speed. And it was relatively slow because of the kind of firepower that the Navy installed on these boats. 

Ultimately, the Idaho and her fellow New Mexico-class battleships would have limited use in the Second World War for the Navy after the Navy came to favor aircraft carriers over battleships, the relatively slow speed of the New Mexico-class battleships meant they could not effectively protect the aircraft carriers.

Deployed in 1919, this battleship would not see heavy action until the Second World War erupted. At that point, these boats had been upgraded with newer technologies. But their relatively slow speed remained. While the Idaho, along with its sister warships, had been assigned to the Pacific Fleet in 1941, they were quickly transferred to the Atlantic Ocean to better prepare the US fleet for war with Germany. 

This move by the Navy inadvertently spared the Idaho and her fellow New Mexico-class battleships from being destroyed by Japan during their air raid on Pearl Harbor on December 7, 1941.

After the Pacific Fleet was gutted by the surprise Japanese attack on Pearl Harbor, though, the Idaho and her fellow New Mexico-class battleships were redeployed to the Pacific Fleet. The Idaho served as the flagship of the Naval task force sent to evict the Japanese from Alaska’s Aleutian Islands in the Spring of 1943. 

Record of Service

Despite her speed limitations, the Navy used the Idaho as a support vessel in various campaigns across the Pacific Theater. She helped support the Marine landings on the Gilbert Islands in September 1943. From there, the BB-42 fought in the Marshall Island campaign, softening up enemy shore positions before the US landings occurred. The Idaho conducted pre-invasion bombardments of Saipan and, later, Guam. 

At the Battle of the Philippine Sea, in which the US Navy obliterated most of the Japanese aircraft capability, BB-42 protected the supply chain supporting the fighting. Idaho bombarded Peleliu, too. Notably, the Idaho assisted in the assaults on Iwo Jima and, inevitably, Okinawa.

In all, the Idaho was the recipient of a whopping seven battle stars for her service to the US Navy in World War II.

Once the war ended, the battleship entered Tokyo Bay as part of the occupation of Japan following the war. After witnessing the signing of the Japanese surrender aboard her cousin battleship, the Missouri, in early September 1945, Idaho made the return trip to the American East Coast where she docked for the last time in Norfolk, Virginia. Idaho was decommissioned on July 3, 1946, she was stricken from the Navy Register on September 16, 1947, and ultimately sold for scrap to Lipsett Inc., of New York City on November 24, 1947.

An ignominious end for such a storied battleship. 

Author Experience and Expertise: Brandon J. Weichert

Brandon J. Weichert, a National Interest national security analyst, is a former Congressional staffer and geopolitical analyst who is a contributor at The Washington Times, the Asia Times, and The-Pipeline. He is the author of Winning Space: How America Remains a Superpower, Biohacked: China’s Race to Control Life, and The Shadow War: Iran’s Quest for Supremacy. His next book, A Disaster of Our Own Making: How the West Lost Ukraine, is due October 22 from Encounter Books. Weichert can be followed via Twitter @WeTheBrandon.

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