The post’s link is to the summary of the research report, and the full 100-page report is linked to at the top of the page.

Here’s the summary:

Escalation in the War in Ukraine

Lessons Learned and Risks for the Future

Despite the devastating losses experienced by the Russian military and both the Ukrainian military and civilian population following Russia’s February 2022 invasion of Ukraine, both sides have refrained from pursuing several escalatory options to date. Although Russia has escalated its attacks on Ukraine in several ways, including strikes against critical infrastructure and the civilian population, it has refrained from other options—notable given the high stakes for the Kremlin and the potential capabilities Russia could bring to bear in the conflict. However, if Russian territorial, personnel, and materiel losses continue to mount without improvements on the battlefield, President Vladimir Putin will face an unpalatable set of choices. In the extreme, the conflict offers plausible scenarios for Russia to become the first state to use nuclear weapons in warfare since 1945. This report evaluates the potential for further escalation in the conflict in Ukraine, including the prospects for escalation to Russian nuclear use. It does so by evaluating Russian and Ukrainian behavior in the conflict to date and identifying and assessing the escalation options still open to both sides. The report is intended to inform U.S. and NATO policymakers as they consider how to avoid further escalation of the conflict while assisting Ukraine in its efforts to defeat the Russian invasion and to better inform the public debate around these issues.

Key Findings

Further Russian escalation has likely been restrained by three main factors

  • The factors are (1) acute concerns for NATO military capabilities and reactions, (2) concern for broader international reactions, particularly the potential to lose China’s support, and (3) the Russian perception that its goals in Ukraine are achievable without further escalation, making risker actions not yet necessary.

Russian escalation to date has seen limited effectiveness

  • None of Moscow’s escalatory measures appear to have altered Ukrainian or NATO behavior in the ways that Putin and his inner circle likely sought. Instead, they have largely hardened Ukrainian and NATO opposition to Russia’s invasion.

Further deliberate escalation, including Russian nuclear escalation, is highly plausible

  • Both Russia and Ukraine may still choose to deliberately escalate the conflict further. Six plausible options for Russian escalation were identified that would have the potential to fundamentally alter the nature of the conflict, ranging from a limited attack on NATO to the use of nuclear weapons against Ukraine. The most likely potential trigger for Russia to escalate the conflict is a perception that battlefield losses are threatening the security of its regime.

Russian nuclear use could be surprisingly extensive

  • Should Russia decide to use nuclear weapons, it may be relatively unrestrained in their employment inside Ukraine.

Inadvertent escalation risks persist

  • Inadvertent escalation could still occur as a result of military activities that are commonplace on both sides but happen to lead to different outcomes. The longer the conflict drags on, the more such risks will accumulate.

Recommendations

  • U.S. and allied policymakers should prioritize maintaining Alliance cohesion regarding the escalation risks of providing support to Ukraine. Doing so is vital both for ensuring long-term support for Ukraine and for maintaining deterrence of Russian aggression against NATO members.
  • U.S. and allied policymakers should carefully evaluate the trade-offs between enhanced support for Ukraine, including the provision of weapons systems with longer ranges, and managing escalation risks, which may become more acute over time.
  • U.S. and allied policymakers should be prepared to interrupt escalatory spirals from more-intensive Ukrainian attacks inside Russia.
  • U.S. and allied policymakers should robustly plan for how to respond to further Russian escalation, including by prioritizing the maintenance of diplomatic and military communication channels with Russia that could become vital to arrest an escalatory spiral.