The ship bears the same name as the World War II-era Kaga, the Tosa-class battleship turned aircraft carrier that was produced in 1928 and participated in the attack on Pearl Harbor.

Kaga was built as part of a wider Japanese military buildup, triggered by heightened Sino-Japanese tensions regarding the contested ownership of the Senkaku Islands.

Like the Izumo, Kaga features no ski-jump ramp for aircraft takeoff, instead using a long flat flight deck, in a similar manner to the US Wasp-class and America-class amphibious assault ships.

[11] In 2010, Forecast International reported that it looked like some original design features were intended to support fixed-wing aircraft, such as the Bell-Boeing V-22 Osprey and Lockheed Martin F-35 Lightning II;[12] as of 2019, both Kaga and Izumo are scheduled to be refit to accommodate the F-35B STOVL variant during their sequential overhauls, which will take five-years, starting in 2022.

[15][16] In 2019, it was reported that Prime Minister Shinzo Abe approved a ¥26.2 trillion (US$238.72 billion) five-year defense budget, which included the upgrade of Izumo and Kaga and the purchase of a combined 147 F-35A and F-35B stealth fighters.

[17] According to the newspaper Mainichi Shimbun, the Japan Air Self-Defense Force (JASDF) is planning to acquire a total of 42 F-35B variants: introducing 18 by FY2023, six in FY2024 and two in FY2025.

[19] Kaga toured the South China Sea and the Indian Ocean during the Indo Southeast Asia Deployment (ISEAD) exercise in 2018 to bolster Japan's presence in geostrategic waters, eventually sailing to the Philippines, Singapore, Indonesia, India, and Sri Lanka.

During his visit, Trump made a speech in which he claimed that many of the United States's allies were taking advantage of its high defense budget by not spending enough on their militaries.

[10] Between October and November 2024, Kaga conducted F-35B Lightning II Joint Strike Fighter developmental tests off the coast of California in preparation for the arrival of Japan's own F-35Bs.