The Lexington-class battlecruisers were officially the only class of battlecruiser to ever be ordered by the United States Navy. While these six vessels were requested in 1911 as a reaction to the building by Japan of the , the potential use for them in the U.S. Navy came from a series of studies by the Naval War College which stretched over several years and predated the existence of the first battlecruiser, (a series of proposed battlecruiser designs was in fact submitted to the General Board in 1909 but was not approved for construction). The fact they were not approved by Congress at the time of their initial request was due to political, not military, considerations.
The Lexingtons were included as part of the Naval Act of 1916. Like the battleships also included in the 1916 Act, their construction was repeatedly postponed in favor of escort ships and anti-submarine vessels. During these delays, the class was redesigned several times; they were originally designed to mount ten 14-inch guns and eighteen five-inch guns on a hull with a maximum speed of , but by the time of the definitive design, these specifications had been altered to eight 16-inch guns and sixteen six-inch guns, with a speed of to improve hitting power and armor (the decrease in speed was mostly attributed to the additions of armor).
The design challenges the Navy's Bureau of Construction and Repair (C&R) faced with this class were considerable, as the combined requirements of optimum hitting power, extreme speed and adequate protection taxed the knowledge of its naval architects and the technology of the time. The desired speed of 35 knots had been attained previously only in destroyers and smaller craft. To do so with a capital ship required a hull and a power plant of unprecedented size for a U.S. naval vessel and careful planning on the part of its designers to ensure it would have enough longitudinal strength to withstand bending forces underway and the added stresses on its structure associated with combat. Even so, it took years between initial and final designs for engine and boiler technology to provide a plant of sufficient power that was also compact enough to allow a practical degree of protection, even in such large ships.
While four of the ships were eventually canceled and scrapped on their building ways in 1922 to comply with the Washington Naval Treaty, two ( and ) were converted into the United States' first fleet carriers. Both saw extensive action in World War II, with Lexington conducting a number of raids before being sunk during the Battle of the Coral Sea and Saratoga serving in multiple campaigns in the Pacific and the Indian Ocean. Though she was hit by torpedoes on two different occasions, Saratoga survived the war only to be sunk as a target ship during Operation Crossroads.
Background
Armor or speed As early as 1903, questions arose in the Naval War College (NWC) Located in Newport, Rhode Island, the Naval War College (NWC) is the education and research institution of the United States Navy that specializes in developing ideas for naval warfare and passing them along to officers of the Navy about the overall effectiveness of large armored cruisers such as the - and vessels just then coming into service. The NWC's 1903 annual summer conference report, which included a staff memorandum on all-big-gun capital ships, also suggested a new type of cruiser that would be armed and armored much like a battleship. The following year, the summer conference considered tactics for a ship armed with four , twenty-two guns, four submerged torpedo tubes and battleship-type protection. Ships such as these were essentially Tennessee-class ships in which the intermediate battery had been traded for heavier main guns and protection. These ships figured in the college's studies for several years, and its 1906 summer conference report on a US building program strongly advocated the ships' construction for use in scouting and as fast wings in a fleet action, and for their resistance to 12-inch gunfire (much greater than the Tennessee class). Although the General Board and the Secretary of the Navy refused to adopt the proposed new armored cruiser, perhaps because the Navy already had 10 new armored cruisers on hand, the college continued to test the design against a variety of foreign vessels, including the British .Friedman (1984), p. 61
By 1908, the summer conference had come to favor battlecruisers over armored cruisers. The increasing range of torpedoes and the distances at which future gun battles were expected to be fought seemed to favor speed over armor. Gunnery officers "laid great stress upon the value of getting the range first and then smothering, or beating down, the enemy's fire before he gets the range." The conference concluded that battlecruisers would be worth building, with the caveat that they be considered in the same category as armored cruisers, in support of the battle fleet but not to fight in the line with fully armored battleships. A majority report recommended a top speed of at least 20 percent above that of battleships. As U.S. battleships then being built were expected to steam at , this meant a minimum speed for battlecruisers of . The Bureau of Construction and Repair (C&R) sketched out such ships the following year, at the request of the Secretary of the Navy, as fast equivalents of the ships being considered. By adopting a hull on a displacement of , it could produce a vessel that could travel at and carry eight 50-caliber 12-inch guns in four twin turrets and equivalent armor; the savings in weight from eliminating two of the Wyomings six turrets more than balanced the added length and height of the armor belt. An enlarged belt was required by a deeper hull, as all American battlecruiser studies required deep hulls to retain their girder strength because those hulls had to be abnormally long to attain their speed. If the armor belt were reduced by an average of three inches, a fifth turret could be added. Four intermediate proposals included one with intermediate armor and eight 12-inch guns and one with Wyoming armor and six 12-inch guns. None of these designs included superfiring turrets. The General Board retained these sketches but did not recommend construction.Friedman (1984), pp. 61–62
Pacific developments As the NWC continued its studies, the Imperial Japanese Navy (IJN) scored a decisive victory over the Russian Baltic Fleet at the Battle of Tsushima in 1905. Japan had already been a concern of the U.S. Navy. Strategist and Admiral Alfred Thayer Mahan had warned then-Assistant Secretary of the Navy Theodore Roosevelt in 1897 of a much greater likelihood of conflict in the Pacific than in the Atlantic. Roosevelt himself, as President of the United States, had written before Tsushima to British diplomat Cecil Spring Rice, "The Japs interest me and I like them. I am perfectly well aware that if they win out it may possibly mean a struggle between them and us in the future."Cooper (2009), p. 208 Tsushima sealed the outcome of the Russo-Japanese War in Japan's favor, signaled its emergence as a world power and began a period of rivalry with the United States over intentions in the Pacific theater, as the two now became the dominant military powers there.O'Brien (2007) pp. 28–29 An immediate consequence was the four armored cruisers, laid down between 1905 and 1908. These ships were designed to carry four guns, a size generally allocated to capital ships and unprecedented for armored cruisers. They would be protected with of belt and turret armour and of deck armour and be capable of a speed of 20.5 knots. The Tsukubas were intended to take the place of aging battleships and thus showed Japan's intention of continuing to use armored cruisers in fleet engagements. They were also exactly the type of ships for which the college had argued unsuccessfully to add to the U.S. Navy before switching to battlecruisers.Burr (2008) pp. 22, 24Osborne (2004), p. 73Perras (2003), p. 8
Therefore, while the Navy did not react as Germany and Britain built increasing numbers of battlecruisers, it took a very different tack when Japan laid down its first ship of this class, , in Britain on 17 January 1911. On 13 June, U.S. Naval Intelligence confirmed she was to be the first of four ships, the other three to be built in Japan, which would form a fast division for the IJN. The following day, the Secretary of the Navy asked the General Board to consider the construction of American battlecruisers for Pacific service, as the Pennsylvanias and Tennessees would no longer be viable units in the face of such opposition. The General Board, not willing to forego battleship construction in favor of auxiliary types such as battlecruisers, balked. On 29 August, it suggested that C&R research a ship under 30,000 tons that could steam at , carry eight and twenty-four guns and have a protective system comparable to the s. In other words, the board requested an American version of the Kongō.Friedman (1984), p. 62Morison and Polmar (2003), p. 70The Kongōs would be cited a second time, almost 30 years later and this time by the General Board, as reason to build the fast battleships (Friedman (1985), p. 307).
In view of the board's lack of urgency, C&R took nearly a year to research this project. The proposed main battery of eight 14-inch guns was kept constant while other factors were calculated—speeds of 26, 29 and 32 knots; operating ranges of 5000, 7000 and 8000 miles; and belt armor of 8, 11 and 14 inches. On 12 July 1912, Naval Constructor R.H. Robinson presented these studies at a lecture he gave at the Naval War College with the General Board in attendance. There, he emphasized 8 inches as an absolute minimum for armor protection and recommended a radius of 8000 miles, the same as in U.S. battleships. The General Board's reaction was to request two battlecruisers for the 1914 Naval Building Program and ask C&R for a slightly modified version of the proposed ship, but the Naval War College felt the design had serious problems and that a fast battleship would be a more practical option.Friedman (1984), pp. 62–64
There was also the political climate to consider—and the weather was not good for battlecruisers. Just as it was thought that Congress would not approve any battlecruisers without reducing the number of battleships, the Navy decided that battleships, such as the new "super-dreadnought" whose construction had just begun, were more important since Congress—in the Navy's eyes—was not approving enough battleships.Gardiner and Gray (1984), p. 119 In 1903 the General Board assumed that the U.S. would build two battleships per year, but Congress "balked", approving just one ship in 1904 (fiscal year 1905), two ships in 1905 (FY 1906), one ship in both 1906 and 1907 (FY 1907–1908), and one ship in both 1912 and 1913 (FY 1913–1914). The approval of two ships in 1910 (FY 1911) instead of just one was apparently "something of a personal triumph for Secretary of the Navy von Lengerke Meyer."Friedman (1985), p. 101
Five years later—with World War I raging in Europe—the political climate had changed. A tentative five-year program put together in October and supported by President Woodrow Wilson called for ten battleships, six battlecruisers and ten destroyers to be completed by 1922. This was submitted to Congress in December 1915. On 2 June 1916, the House of Representatives passed the bill in a modified form, replacing five of the battleships with battlecruisers. On 29 August 1916, the Senate also passed an altered bill, keeping the original number of ships but stipulating that the program be completed in three years (FY 1917–19). The first four ships were paid for in FY 1917, the fifth in FY 1918, and the last in FY 1919.Friedman, U.S. Cruisers, pp. 71–72