The victory of the Royal Navy at the Battle of Taranto was a pivotal point as this was the first true demonstration of naval air power. The importance of naval air power was further reinforced by the Attack on Pearl Harbor, which forced the United States to enter World War II. Nevertheless, in both Taranto and Pearl Harbor, the aircraft mainly attacked stationary battleships. The sinking of the British battleships and , which were in full combat manoeuvring at the time of the attack, finally marked the end of the battleship era. Aircraft and their transportation, the aircraft carrier, came to the fore.