What is most striking about discussions about sanctions is the way officials talk about what the negative effects of really serious sanction would be on their economies or the international financial system, as if the alternative were a simple continuation of the status quo.

The real comparison they should be making is between the effects of the sanctions, if they are adopted, and the effects on their economies of a major ground war in Europe with the attendant risks of escalation to nuclear war, if they are not.

A nuclear war could have a really negative impact on their economies.

Moreover, everyone should bear in mind that once a war begins, all the assumptions of the “rational actor” paradigm no longer hold, if they ever did even to a limited extent. The rational calculation of costs and benefits would be out the window, as would be the ability of any leader, even Putin, to control the course of events. We should recall the 1962 Cuban Missile Crisis, and how dicey that was.

We should also recall how, in the run-up to World War I, the mobilization of Russian military units set in motion forces that could not be controlled, leading to the outbreak of hostilities in August, 1914.
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Three critical questions have received little attention:

1) First, if Russia invades Ukraine and a war ensues, how will the war be stopped?

2) Second, if Russia invades Ukraine, how will the risks of accidental or intentional escalation be moderated? If such escalation occurs, in the fog of war, how will the risks of further escalation to nuclear war be controlled? Could the Security Council play a useful role, now, by debating a draft resolution which takes those risks into account?

Assuming Russia would veto any such resolution, should members be preparing, now, to take that Resolution to the General Assembly and bring it to a vote?

3) The third question is whether countries should think, now, about forming a “great coalition” to bring military force and other power to bear in forcing Russian troops out of Ukraine? This is precisely what members of the United Nations did in 1990, when they joined a military coalition to use force, in exercise of the right of collective self-defense, and repelled Saddam Hussein’s Iraqi forces following their invasion and occupation of Kuwait.

Kuwait was not a member if NATO. Yet the countries of the world felt it was important to defend the territorial integrity of Kuwait and the bedrock prohibition against the international use of force enshrined in article 2 (4) of the Charter.

Repelling aggression by a nuclear power which is a Permanent Member of the Security Council would represent an unprecedented challenge. How would that work out?