The U.S. homeland missile defense program has a history of changes, cancellations, and downsizing—evolving from a bold plan to defend against any nuclear missile to today’s modest program able to defend against a limited North Korean attack. Our current, deficient system has resulted not only from technological and programmatic difficulties but also from national missile defense policies that have vacillated from bold to feeble. Today, programmatic challenges continue to leave the future of homeland missile defense uncertain.