The Japanese Defense Ministry has expressed its plans to supplement its six existing Kongo and Atago class destroyers with two additional units, which like their predecessors will also feature the Aegis system.
Japan currently has four Kongo class destroyers, which are roughly based on the Arleigh Burke class and two improved versions known as the Atago class. The Kongo class ships were commissioned between 1993 and 1998 and the Atago class between 2007 and 2008.
The two new ships will be fitted with hit-to-kill SM-3 missiles to defend against ballistic missile attacks. Both the current SM-3 Block 1A and the next-generation SM-3 Block IIA, a joint development between Japan and the United States, will be integrated.
The SM-3 Block IIA recently completed its design phase and is expected to be available for testing in 2015. The new version will feature the ability to intercept longer-range ballistic missiles and from further out than is currently possible with the existing SM-3 Block 1A/B.
Japan is also looking at introducing the ground-based version of the SM-3 in addition to the naval version. Also under consideration is the Terminal High Altitude Area Defense (THAAD) missile system which has already been purchased by the United Arab Emirates in 2011.
Both system would complement the current Patriot Advanced Capability 3 (PAC-3) missile units in Japan, which have a much shorter range than the longer-ranged SM-3 and THAAD that can cover a greater area.
The new plans are the latest in a long line of recent moves that seek to comprehensively increase Japan's military strength against countries in the region such as North Korea and especially against China with which Japan is involved in an ongoing territorial dispute regarding the Senkaku / Diaoyu Islands.