Horizontal escalation: an asymmetric approach to Russian aggression?

ENThis article examines whether horizontal escalation strategies—threats to geographically expand a conflict—can help deter Russian aggression or manage escalation in a US/NATO-Russia crisis. After summarizing the current pitfalls of conventional and nuclear deterrence strategies in Eastern Europe, the article highlights horizontal escalation’s brief prominence in US Cold War strategy. It then develops and applies a simple analytic framework to four examples of horizontal escalation options in the context of a crisis over Russian aggression in the Baltic region: strikes on Russian forces deployed in Syria; interdiction of Russian ships and seaborne commerce; strikes on bases in Russia’s Far East; and an invasion of Crimea. The analysis ultimately yields a skeptical view of horizontal escalation, yet finds a limited role for it in the US/NATO strategic toolkit. Under most circumstances, its costs and risks appear likely to outweigh its benefits. Its promise of coercing or distracting Russian leaders in a Baltic crisis is highly constrained. However, horizontal escalation’s potential benefits for deterrence before a crisis and signaling during a crisis justify greater attention and planning than they have received to date.