Michael Kimmage for War on the Rocks in connection with the American decision to provide anti-tank missiles to Ukraine:

Both sides interpret their own actions as defensive. The greater the need to defend from the other’s aggression, the more an expansion of military assets makes sense — hence, the provision of “defensive lethal weapons.” Hence, Russia, chooses to intensify its military presence in Kaliningrad and near the Baltic states. The greater the aggregate military presence, the more opportunity there is for an incident, an American-supplied weapon, say, that can be shown killing Russian or ethnic Russian civilians or purportedly shown doing this. Or the incident could involve Russian troops traveling by rail through Lithuania to Kaliningrad, behaving in a way that suggests malign intent. Once public opinion is inflamed, in Russia or in the West, it would require exceptionally cool heads to retain control of the decision-making process.

Neither Washington nor Moscow wants direct military conflict, but this sentiment on its own is inadequate to preventing it. The prevention of conflict demands regular communication and proactive diplomatic effort. Khrushchev may have thought he was supplying Cuba with “defensive” nuclear weapons in 1962. President John F. Kennedy was willing to understand Soviet motivations as defensive enough not to attack Cuba. In the end, both he and Khrushchev got lucky. They could have sleepwalked into mutually assured destruction. After the Cuban missile crisis, U.S.-Soviet diplomacy was stepped up. We are now at risk of reverting back to a pre-Cuban missile crisis Cold War, another long, twilight struggle.