Biden’s team needs new thinking on how missile defense affects the long-term balance of strategic advantage in peacetime, crisis, and war with different opponents. Is the Cold War concept of strategic stability useful for framing US relations with Russia and China? If so, how should it account for new technologies like hypersonic cruise missiles, warfighting domains like cyber and space, and linkages between nuclear and conventional conflicts? Are there tradeoffs between efforts to reduce nuclear risks from major powers versus regional actors? What role should an integrated, layered missile defense system play in a US theory of victory for regional conventional wars under the nuclear shadow? How should US defense posture be sized to avoid arms races and crisis instabilities?

To explore new arms control options, Biden should break with the policies of Bush, Obama, and Trump. Like Nixon, he should be prepared to negotiate with rivals limits on US missile defense ambitions in the interests of national security and international stability.

Biden cannot reverse the new era in missile defense, which is marked by Trump’s words but ultimately defined by the new strategic problem of major power competition. However, Biden’s team can develop a clear and balanced approach to missile defense that aligns US and allied capabilities with the president’s promises to meet future challenges, and that grounds policy in “fact and science” and strategic thinking.