America Needs to Update Its Missile Defense Strategy

The strategic role of the U.S. missile defense should be fundamentally reassessed.

Washington and Seoul are planning to deploy U.S. missile defenses on South Korean soil in response to North Korea’s nuclear and rocket tests this year. The talks come after U.S. and NATO officials announced the completion of a new U.S. ballistic missile defense site in Romania—a key element of a joint NATO system—that aims to protect Europeans against missiles from Iran but not from Russia. The two sites are part of an evolving U.S. global missile defense network.

The United States justifies multibillion-dollar investments in missile defense technology because it believes that the capability to defend against ballistic missiles will, overall, help reduce nuclear risks to the United States and its allies in the twenty-first century. This conclusion is at the core of the current U.S. missile defense posture, known as the 2010 Ballistic Missile Defense Review (BMDR), and many believe it still holds. But its three basic premises are being challenged by a shift in the strategic environment.

The first premise was that nuclear risks posed by regional actors had increased, and new missile defense technology could help mitigate these risks. Defenses against limited missile attacks could deter and defend against states like Iran and North Korea, armed with nuclear missiles and exploiting nuclear blackmail strategies. Defense capability was necessary because, according to the BMDR, “deterrence by threat of strong offensive response may not be effective” against these new actors.

Today, North Korea remains a serious concern. Iran, less so. The recent deal to limit Iran’s nuclear capability reduces the need to defend against an Iranian nuclear bomb. To be sure, the nuclear agreement says nothing about ballistic missiles—Iran tested another one in October 2015. But there is little strategic value for Tehran to launch conventional missiles at European capitals, particularly if political relations with the West improve.

While Tehran denies seeking a bomb, Pyongyang desperately wants the world to fear its fledgling nuclear weapons capability. North Korea conducted a fourth nuclear test on January 6 and a long-range rocket test on February 7.

The second premise was that, in 2010, the nuclear risks posed by Russia had significantly decreased relative to the Cold War. Although Russia still had a large nuclear arsenal, it did not threaten to use it. The BMDR states that the United States and Russia are “no longer enemies” and there is “no significant prospect of war between them.” Consequently, while the United States must continue to ensure “strategic stability with existing nuclear powers,” this “more familiar challenge” is no longer top priority, the nuclear posture explains.

After Russia’s annexation of Crimea in 2014, this assessment changed significantly. The risk of military confrontation in Eastern Europe has increased, and with it, the risk of nuclear use. “We need a new playbook” to deter Moscow’s “malign and destabilizing influence, coercion and aggression,” U.S. Secretary of Defense Ash Carter said on October 14, 2015.

The third premise was that U.S. missile defense deployments need not increase nuclear risks among major powers, even though both Russia and China strongly opposed the U.S. program. Russia has claimed for over a decade that American global defenses would undermine strategic stability. Moscow warned of a new arms race and threatened military countermeasures if Washington didn’t limit its efforts.