An aircraft carrier is a massive warship that functions as a mobile, seagoing airbase, equipped with a full-length flight deck to launch and recover aircraft, and has evolved from early 20th-century balloon platforms into nuclear-powered supercarriers carrying dozens of fighters. As the largest weapon system ever created, it has replaced the battleship as the fleet's flagship since World War II, transforming naval combat into beyond-visual-range air strikes while offering strategic advantages by operating in international waters without territorial interference. These vessels are crucial for power projection, deterrence, and diplomacy—as evidenced by Henry Kissinger's famous quip that "an aircraft carrier is 100,000 tons of diplomacy," and Admiral Sir Mark Stanhope's assertion that countries aspiring to strategic influence require them. As of August 2026, there are 50 active carriers operated by fifteen navies, with the United States dominating the field with 11 large nuclear-powered fleet carriers whose combined deck space exceeds that of all other nations combined. To be effective, these ships must exceed 30 knots to evade submarines and generate wind over the deck, while also being versatile enough to handle missions ranging from humanitarian aid and disaster relief to defensive counter-air and amphibious assault support.