While the Japanese fleet pounded Pearl Harbor, other Imperial Forces were invading Malaya, Guam, and Wake Island simultaneously (Pearl Harbor is to the east of the International Date Line while Malaya, Guam, and Wake are west of it. History books say Pearl Harbor was attacked on 7 Dec 1941, whereas the other places were invaded on the 8th. Although strictly correct, the events happened within the same time frame).
The Price of Wales battleship and the Repulse battlecruiser sailed to repel the Japanese invasion fleet that landed in Kota Bharu, Malaya. On 10 December, 60 Japanese Mitsubishi G3M2 (“Nell”) (see the picture) and 26 Mitsubishi G4M1 (“Betty) caught the British capital ships without air protection (a squadron of Buffaloes arrived late to protect the ships).
Both ships sank quickly with heavy loss of life after receiving 4 torpedo hits each. This was the first time that capital ships of any country had been sunk in open seas by air attack.
A few days ago, 4 American battleships had been sunk and another 4 damaged while in port. In November 1940, British Swordfish seriously damaged 3 Italian battleships in the port of Taranto.
The Luftwaffe damaged capital ships in open seas but failed to sink them (i.e., the aircraft Carrier Illustrious, and battleships Warspite, Valiant, and Barham, all of them in 1941). The British damaged the Bismarck in 1940 but also failed to sink it. Cruisers and destroyers had been sunk during the war by air attack, but the big ships were hard nuts to crack. After the successful attack of the Japanese air arm, British, German, and American aircraft found success against the big ships.
The G3M2 design gave priority to range. Designers did not incorporate armor or self-sealing fuel tanks. Structurally, the aircraft was not robust. It was a vulnerable airplane able to carry only 800 kgs of bombs. But its operational radius was spectacular: 1450 km. It gave a good account of itself until replaced by better bombers.