Alaska Class Cruiser - "Large Cruisers" or "battlecruisers"?

"Large Cruisers" or "battlecruisers"?

Early in its development, the class used the designation CC, which signified that they were to be battlecruisers in the tradition of the Lexington class; however, the designation was later changed to CB to reflect their new name, "large cruiser", and the practice of referring to them as battlecruisers was officially discouraged. The U.S. Navy then named the individual vessels after U.S. territories, rather than states (as was the tradition with battleships) or cities (for which cruisers were named), to symbolize the belief that these ships were supposed to play an intermediate role between heavy cruisers and fully-fledged battlecruisers.

They resembled contemporary battleships in appearance, weighed only 5,000 tons less in displacement, mounted the familiar 2-A-1 main battery, shared a similar massive columnar mast, and carried 5"/38 caliber dual-purpose guns. Although the battleships carried eight (older refitted ships) or ten (post-South Dakota) 5"/38 twin mounts flanking the superstructure, the Alaska cruisers only carried six: one at each of the four superstructure corners, and one each at fore and aft on the centerline.

There are two main arguments for referring to the Alaska class as "large cruisers". The first is their armor; while they were able to withstand more fire from guns than any other cruiser afloat, they were virtually defenseless against torpedoes because they had no anti-torpedo scheme. The lack of underwater protection would also make them vulnerable to shells which fell slightly short of their mark and continued underwater to hit the hull. In addition, their armor was only marginally capable of stopping 12" fire; they were vulnerable to battleship fire (14–16" fire) at any range. The second argument lies entirely in their design. The design of the Alaska class ships was, from the keel up, just a scaled-up treaty cruiser unencumbered by the Washington, London and Second London naval treaties. In addition, despite being much larger than the Baltimore class, the secondary battery of the "large cruisers" was only slightly larger. Whereas the Alaska class carried twelve 5"/38 caliber, fifty-six 40 mm, and thirty-four 20 mm guns, the Baltimore class carried the same number of 5"/38s, eight fewer 40 mm, and only ten fewer 20 mm. In addition to all of this, author Richard Worth remarked that when they were finally completed, launched, and commissioned, they had the "size of a battleship but the capabilities of a cruiser".

Despite these cruiser-like characteristics, and the U.S. Navy's insistence on their status as cruisers, the Alaska class were frequently described as battlecruisers at the time. The official navy magazine All Hands said "The Guam and her sister ship Alaska are the first American battle cruisers ever to be completed as such." Some modern historians take the view that this is a more accurate designation because they believe that the ships were "in all sense of the word, battlecruisers", with all the vulnerabilities of the type. The traditional Anglo-American battlecruiser concept had always sacrificed protection for the sake of speed and armament, meaning they were not intended to stand up against the guns they themselves carried. The Alaska's percentage of armor tonnage, 28.4%, was slightly less than that of fast battleships; the British King George V class, the American Iowa class, and the battlecruiser/fast battleship HMS Hood all had armor percentages between 32 and 33%, whereas the Lexington-class battlecruiser design had a nearly identical armor percentage of 28.5%. In fact, older battlecruisers, such as the Invincible (19.9%), had a significantly lower percentage. In terms of displacement, the Alaska class was about twice as heavy as the newest heavy cruisers (the Baltimore class). In addition, they had much larger guns; while the Alaska class carried nine 12"/50 caliber guns that were as good as, if not superior to, the old 14"/50 caliber gun used on the U.S. Navy's pre-treaty battleships, the Baltimore class only carried nine 8"/55 caliber Marks 12 and 15 guns.