Japan will spend some $4.2 billion over the next 30 years on installing and operating US radar systems to protect itself against North Korean missile threats. The latest move by Tokyo to upgrade its military was announced by Defense Minister Itsunori Onodera, AFP reports. Japan sees the North’s nuclear weapons and ballistic missiles as a direct threat. “Our country’s ballistic missile defense capacity will significantly improve,” Onodera said Monday. “The cost is not fixed yet. We will examine the prices at every level possible,” he added. US firm Lockheed Martin has offered to build the radars needed for a new ground-based Aegis Ashore missile defense system at a cost of roughly 134 billion yen ($1.21 billion) for one unit, Onodera said. The combined expenditure for two units as well as maintenance and operational costs for the next 30 years was estimated at 466 billion yen ($4.2 billion).