This summer marked the ninth occasion on which hit-to-kill missile defense technology proved its worth. The GMD interceptor (which stands for Ground-Based Midcourse Defense) destroyed a target ballistic missile above the earth’s atmosphere in June. This demonstrated once again that hit-to-kill technology works against ballistic missiles and is worth the investment.

Building a strong missile defense is challenging, but it’s not optional. The technology needed to build a long-range, intercontinental ballistic missile (ICBM) was once far out of reach for all but the most highly developed countries. Today, the regimes most hostile to the U.S. are arming up.