Nuclear Deterrence Gap in Europe

Russia has a huge advantage in nuclear arms for use in Europe. In a crisis, Moscow might perceive nuclear superiority and try to exploit it.  Lessening the imbalance may also reassure allies and be essential for any negotiated arms control efforts. 

The Kremlin may think swagger is justified. Russia could have nearly 1,500 tactical and theater nuclear arms, most oriented to the European theater. The U.S. has only about 100 tactical nuclear bombs there, and France about 50 nuclear-armed missiles. All would be delivered by tactical fighter-bombers. The U.S. bombs are part a NATO program that shares nuclear responsibilities among allies. 

The theater imbalance emerged in part from post-Cold War U.S. unilateral  withdrawals and Russia’s nuclear modernization. By comparison, in long-range, or strategic, nuclear forces, the two countries have rough parity. 

The strident hostility of Putin’s Russia heightens nuclear risks. So, too, does a possible decline in allied confidence in U.S. extended deterrence, the “nuclear umbrella.” In 2023, the U.S. Strategic Posture Commission said many allies “perceived no need” to acquire their own nuclear capabilities. This may be changing. Recently, the European Nuclear Study Group warned of the risk of Russian “nuclear coercion” and the “fragility” of U.S. extended deterrence. 

Europeans are speaking out. Chancellor Friedrich Merz says Germany is discussing nuclear cooperation with France and the UK. So is Sweden. Poland is talking with France, and President Karol Nawrocki says his country should develop a security strategy based on “nuclear potential.” Nuclear issues were front and center at the recent Munich Security Conference. There a Pentagon leader reiterated that the U.S. would ”continue to provide” extended deterrence.

NATO members are taking some steps to bolster theater nuclear forces. The U.S. has modernized its nuclear bombs in Europe. The UK plans to deploy a small, land-based nuclear force using F-35s to deliver them. On March 2, President Emmanuel Macron said France may allow “temporary deployment” of nuclear-armed aircraft in allied states as part of a strategy of “forward deterrence.” France and the UK have submarine-based strategic forces, but they are less suited to theater needs. 

The U.S. has deployed low-yield nuclear warheads on long-range Trident ballistic missiles on submarines and might field a nuclear-armed sea-launched cruise missile. They will help but have downsides. Being less visible, sea-based missiles may have less deterrent value. Russian radars may be unable to tell if a Trident in flight has only a low-yield warhead. 

More remedies to the theater gap may be considered. Poland, Sweden, Finland, and other allies might play greater roles in NATO’s nuclear sharing program. If Poland were to host U.S. nuclear bombs, deliverable by its F-35s, this could help counter Russia’s nuclear buildup in Belarus and western Russia. Nuclear missions could be added to a U.S. Army land-based theater missile. 

If confidence in U.S. extended deterrence were to decline further, some allies might seek to develop their own nuclear arms. But this could be expensive, take up to a decade, and draw criticism for undermining the 191-nation Nuclear Nonproliferation Treaty (NPT). 

Multiple allies could develop nuclear weapons. Prior to joining the NPT in 1968, Sweden had a program capable of producing nuclear weapons within a few years. Italy halted nuclear weapons R&D when it joined the NPT in 1975. 

Interest in arms control could resurface. NATO’s missiles in the 1980s gave the U.S. leverage to conclude the path-breaking 1988 Intermediate-range Nuclear Forces Treaty with the USSR. Deployment of a new U.S. land-based theater nuclear missile could be essential for negotiating any arms control accord. 

NATO has a vital interest in reducing the risk that Kremlin leaders might misperceive its nuclear deficiency as weakening extended deterrence. A new Helmut Schmidt-like call for the alliance to do more may be merited. 

William Courtney was deputy negotiator in U.S.-Soviet Defense and Space Talks (missile defense), ambassador to the U.S.-Soviet Commission to implement the Threshold Test Ban, co-chair in early talks with Russia on the safety, security, and dismantlement of nuclear weapons, and ambassador to Kazakhstan, where he helped negotiate the withdrawal of remaining Soviet nuclear forces.