Aegis Ashore

Aegis Ashore is the land-based variant of the Navy’s Aegis Weapons System and the centerpiece of Phases II and III of the European Phased Adaptive Approach (EPAA). The system incorporates land-based versions of the various componants used on Aegis ships, including the deckhouse, AN/SPY-1 radar, the Mark 41 Vertical Launching System (VLS), and Standard Missile-3 (SM-3) interceptors. It is intended to serve as a midcourse defense against medium and intermediate-range missiles. ¹ The first two planned Aegis Ashore sites are at Deveselu, Romania and Redzikowo, Poland. The AN/TPY-2 X-band Radar in Turkey provides early tracking data to the Aegis Ashore sites on missiles launched from the Middle East.

After announcing the EPAA in 2009, the United States negotiated a hosting agreement for Aegis Ashore with Romania and broke ground in 2013. ² The Missile Defense Agency successfully tested the configuration of the Romania site for the first time in December 2015. ³ That same month, the United States and Romania made a “Technical Capability Declaration” for the Deveselu site, which was followed by a declaration of Initial Operating Capacity in May 2016. ⁴ Groundbreaking for the site in Poland took place in 2016 with initial operations planned for 2018. ⁵

Each Aegis Ashore site include three MK 41 VLS tubes with eight cells apiece for a total of 24 interceptors per site. ⁶ The Romania site will use the SM-3 Block IB initially, but both sites are slated to include the SM-3 Block IIA once it becomes operational.

The U.S. Congress directed the Department of Defense to study the potential of deploying air defense assets at Aegis Ashore sites, possibly by arming certain VLS cells with SM-2 or SM-6 interceptors. ⁷ After the North Korean nuclear test in January 2016, PACOM Commander Admiral Harry Harris discussed operationalizing the test Aegis Ashore system at the Pacific Missile Range Facility in Hawaii to defend the islands. ⁸

In December 2017, Japan’s Cabinet approved plans to install two Aegis Ashore systems, scheduled to go into operation by 2023. ⁹ Officials sought to acquire the system to counter North Korea’s ballistic missile threat, as well as China’s advanced cruise missile program, although the former is more commonly acknowledged. In a press conference following Cabinet approval, Japanese Defense Minister Itsunori Onodera explained that “the threat against our national security from North Korea’s nuclear and missile development has become more serious and imminent than before and has risen to a new level,” and that the two Aegis Ashore sites would supplement maritime forces to cover this threat. ¹⁰ Japanese officials had considered both Aegis Ashore and THAAD, with deployment options being either two Aegis Ashore sites (at ¥70-80 billion each) or six THAAD units (at more than ¥100 billion each). ¹¹ Officials chose Aegis Ashore for its wider coverage area and cheaper deployment. Japanese investment in the SM-3 Block IIA and the potential to pair Aegis Ashore with air defenses or even long-range strike options may also have contributed to this decision.