In 1901, the US Navy's battleship designs reflected the prevailing theory of naval combat—that battles would initially be fought at some distance, but the ships would then approach to close range for the final blows, when shorter-range, faster-firing guns would prove most useful. The premier battleship class then under construction carried four large 12-inch (305 mm), eight 8-inch (203 mm), and twelve 7-inch (178 mm) guns, a striking power slightly heavier than typical foreign battleships of the time.
The Naval Institute's Proceedings magazine devoted space in two of its 1902 issues to possible improvements in battleship design. The first article was authored by Lieutenant Matt H. Signor, who argued for a ship with 13-inch (330 mm) and 10-inch (254 mm)/40 caliber guns in four triple turrets. The secondary battery would be composed of 5-inch (127 mm)/60 guns. This paper provoked enough thought that Proceedings published comments on the story from Captain William M. Folger, Professor P. R. Alger and naval constructor David W. Taylor—an up-and-coming officer and future head of the Bureau of Construction and Repair (C&R). These comments expressed doubt that the proposed vessel could be modified into a feasible design, but they praised his thoughts as a step in the right direction. Alger believed that Signor was on the right track in suggesting larger armament, though he thought that triple turrets would be unworkable and eight 12-inch guns in four twin turrets would be a much more realistic arrangement. Naval historian Norman Friedman believes that this was one of the "earliest serious proposals for a homogeneous big-gun battery."
The South Carolina
design began in the United States' previous pre-dreadnought
battleships, such as the preceding Connecticut
class (New Hampshire
The suggestion leading directly to the South Carolina class came from
Homer Poundstone, a Lieutenant Commander in the Navy, who became the principal proponent of an American all-big-gun design. In a December 1902 paper written for President Theodore Roosevelt, he argued for greatly increasing the size of current battleships, although he also supported retaining mixed main batteries.[C] However, by the March and June 1903 editions of Proceedings, Poundstone began advocating for an all-big-gun arrangement, featuring twelve 11-inch (279 mm) guns mounted on a 19,330 long tons (19,640 t) ship. In October of the same year, the Italian naval architect Vittorio Cuniberti presented a similar idea in an article for Jane's Fighting Ships entitled "An Ideal Battleship for the British Navy". He argued in favor of a ship with twelve 12-inch guns on a slightly larger displacement than the battleships in service at the time, 17,000 long tons (17,000 t). He believed that the higher weight would allow 12 inches of armor and machinery capable of propelling the ship at 24 kn (44 km/h; 28 mph). Poundstone used what he believed to be the great popularity for this idea among Europeans to justify the all-big-gun design.
In 1903, Poundstone's designs began receiving attention from American naval authorities. After being refined by Washington Irving Chambers, Poundstone's work was brought to the Naval War College, where it was tested in war games during the 1903
Newport Conference. The results indicated that a theoretical battleship that dispensed with the intermediate 8- and 7-inch armament and was armed with only twelve 11- or 12-inch guns, all able to fire on a single broadside, was worth three of the battleships then in service. According to the men who conducted the tests, the main reasoning for the finding was that the measure of effective gun ranges was directly related to the maximum length of an enemy's torpedo range. At this time, the latter was roughly 3,000 yd (2,700 m); at that distance, the 7- and 8-inch guns common to American intermediate batteries would not be able to penetrate the armor of enemy battleships. Worse still, it was certain that—as the United States was developing a 4,000 yd (3,700 m) torpedo—gun range would have to rise in the near future, making the intermediate guns even less useful. However, a homogeneous main battery of 11- or 12-inch guns would be able to penetrate the armor and have sufficient explosive power to disable an enemy capital ship, and adding as many 3-inch (76 mm) guns as possible would provide a strong defense against torpedo-carrying but unarmored destroyers. As it turned out, events in the Russo-Japanese War soon showed that naval battles could be fought at significantly greater distances than had been thought possible.