Despite being a major producer of military aircraft prior to World War I (WW I), the aircraft industry of Japan was forced to disband post WW II. The authorities then, prohibited R&D related activities and the aircraft industry remained idle. It was in 1952 that the industry again started picking up and rebuilding in phases. Thus, Japan aircraft industry has had a mixed history.
The early efforts were limited to servicing / repairing and supply of spares to the fighting aircraft of the United States, engaged in Korean War. During the Cold War period too, the US helped Japan to rebuild in order to help defend against the Soviet threats. US initially provided Japan with the kit to assemble and later permitted to manufacture under licence.
Over the period, the Japanese majors have built enough experience to produce even a fifth generation modern day fighter today. While the technological prowess of Japan remains undisputed, it is the cost which remains prohibitively high. Since Japan has lifted the export ban in 2014, it is expected that with increase in demand, the cost of production too would get rationalized.
With China too aggressively pushing for indigenous fifth generation fighter aircraft, the East, finally, appears to be gearing up to seriously challenge the predominance of West in the business of fighter aircraft production.
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