Tora! Tora! Tora! (Japanese: トラ・トラ・トラ！) is a 1970 epic war film that dramatizes the events leading up to the Japanese attack on Pearl Harbor in 1941, from both American and Japanese positions. The film was produced by Elmo Williams and directed by Richard Fleischer, Toshio Masuda and Kinji Fukasaku. It features an ensemble cast, including Martin Balsam, Joseph Cotten, So Yamamura, E.G. Marshall, James Whitmore, Tatsuya Mihashi, Takahiro Tamura, Wesley Addy, and Jason Robards. It was Masuda and Fukasaku's first English-language film, and first international co-production.

The tora of the title, although literally meaning "tiger", is actually an abbreviation of a two-syllable codeword (i.e., totsugeki raigeki 突撃雷撃, "lightning attack"), used to indicate that complete surprise had been achieved.

The film was released in the United States by 20th Century-Fox on September 23, 1970, and in Japan by the Toei Company on September 25. It received mixed reviews from American critics, but was praised for its historical accuracy and attention to detail, its visual effects, and its action sequences. Tora! Tora! Tora! was nominated for five Oscars at the 43rd Academy Awards, including Best Cinematography and Best Film Editing, winning Best Visual Effects (L.B. Abbott and A.D. Flowers). The National Board of Review ranked it in its Top Ten Films of 1971. A 1994 survey at the USS Arizona Memorial determined that for Americans the film was the most common source of popular knowledge about the Pearl Harbor attack.

In September 1940, following a severe trade embargo imposed on a belligerent Japan by the United States a year prior, influential Japanese army figures and politicians push through an alliance with Germany and Italy, despite opposition from the Japanese navy, and prepare for war. The newly appointed Commander-in-Chief of the Combined Fleet, Admiral Isoroku Yamamoto, reluctantly plans a pre-emptive strike, believing Japan's best hope of controlling the Pacific Ocean is to quickly annihilate the American Pacific fleet anchored at Pearl Harbor. Air Staff Officer Minoru Genda is chosen to mastermind the operation, while his old Naval Academy classmate Mitsuo Fuchida is selected to lead the attack.

In Washington, U.S. military intelligence has broken the Japanese Purple Code, allowing them to intercept secret Japanese radio transmissions indicating increased Japanese naval activity. U.S. Army Colonel Rufus S. Bratton and U.S. Navy Lieutenant Commander Alwin Kramer monitor the transmissions. At Pearl Harbor, Admiral Husband E. Kimmel increases defensive naval and air patrols around Hawaii. General Walter Short orders aircraft concentrated on the airfield runways to avoid sabotage by enemy agents, while some planes are dispered to other airfields on Oahu.

Diplomatic tensions escalate as the Japanese ambassador to Washington continues negotiations to stall for time. Bratton and Kramer learn from intercepts that the Japanese planned 14 radio messages from Tokyo to their embassy in Washington with orders to destroy their code machines after receiving the final message. Deducing the Japanese will launch a surprise attack after the messages are delivered, Bratton tries warning his superiors. However, Chief of Naval Operations Harold R. Stark is indecisive over notifying Hawaii without first alerting President Franklin D. Roosevelt, while Army Chief of Staff General George Marshall's order that Pearl Harbor be alerted of an attack is stymied by poor atmospherics that prevents radio transmission and a warning telegram not marked urgent. The Japanese fleet launches its aircraft at dawn on December 7. Two radar operators detect their approach to Hawaii, but the duty officer Lieutenant Kermit Tyler dismisses their concerns. Similarly, the claim by the destroyer USS Ward to have sunk a Japanese miniature submarine off the entrance to Pearl Harbor is dismissed as unimportant. The Japanese achieve total surprise, which Commander Fuchida indicates with the code signal "Tora! Tora! Tora!"

The damage to the naval base is catastrophic and casualties are severe. Several battleships are either sunk or heavily damaged. General Short's anti-sabotage precautions allow Japanese aircraft to easily destroy American planes on the ground. In Washington, a stunned Secretary of State Cordell Hull is asked to receive the Japanese ambassador Kichisaburō Nomura. The 14 part message – including a declaration that peace negotiations were at an end – was meant to be forwarded to the Americans thirty minutes before the attack, but the Japanese embassy failed to decode and transcribe it in time. The attack started while the two nations were technically still at peace. The distraught Nomura, helpless to explain the late ultimatum and unaware of the ongoing attack, is rebuffed by Hull.

The Japanese fleet commander, Vice-Admiral Chūichi Nagumo, refuses to launch a scheduled third wave of attack aircraft for fear of exposing his fleet to U.S. submarines. General Short and Admiral Kimmel belatedly receive Marshall's telegram warning of impending danger. Aboard his flagship, Admiral Yamamoto informs his staff that their primary target – the American aircraft carriers – were not at Pearl Harbor, having departed days previously. Lamenting that the declaration of war arrived after the attack began, Yamamoto notes that nothing would infuriate the U.S. more and concludes: "I fear all we have done is to awaken a sleeping giant and fill him with a terrible resolve."