M101 howitzer

The 105 mm Howitzer M2A1(M101) was the standard light field howitzer for the United States in World War II, seeing action in both European and Pacific theatres. Entering production in 1941, it quickly entered the war against the Imperial Japanese Army in the Pacific, where it gained a reputation for its accuracy and powerful punch. The M101 fired 105 mm high explosive (HE) semi-fixed ammunition and had a range of 11,200 metres (12,200 yd), making it suitable for supporting infantry.

M101 howitzer in Days of Infamy
The M101 was the most strongest field gun the US Forces could field when the Japanese invaded Hawaii in 1941. Fletch Armitage manned one of these guns during the battle, and even managed to knock out a Japanese Tank. Despite its superior fire power, it still wasn't enough to prevent the loss of Hawaii to the Japanese.