Antimissile capabilities have advanced far beyond the brute-force systems of the 1960s or the science-fictionesque concepts of the 1980s. Decades of research are paying off as effective systems are moving into the field. Once-exotic technologies are poised to change the balance of power between rogue nations exploiting ballistic missile proliferation and the democracies they threaten with missile attack.
A key Pacific ally of the United States has become the first foreign nation to field a sea-based ballistic missile interception system. The technology is a modification of the Aegis air defense weapons system designed to track and destroy short- and intermediate-range missiles. This capability permits Japanese warships to defend their island nation from attack by neighboring states.