The Doctrine of Proportionality: Star Trek “Balance of Terror”

In Star Trek “Balance of Terror” a Romulan ship destroys four “Earth Outpost Stations” that border the Neutral Zone, a demilitarized region of space. The Captain of the Enterprise, James T. Kirk (William Shatner), must decide what to do after this “unprovoked attack.” Kirk’s response to the Romulan attack is based on the doctrine of proportionality: “a state is legally allowed to unilaterally defend itself and right a wrong provided the response is proportional to the injury suffered. “¹ An important theme in the episode is a proportional response to an unprovoked attack can prevent a full-scale war.

Following the Romulan attack, Doctor McCoy (DeForest Kelley) is the voice of pacifism. He is against attacking the Romulans, suggesting that it will violate the peace treaty and lead to war. However, a non-response would only increase the likelihood of war. By refusing to use military force in response to an unprovoked attack, a lasting peace is rarely achieved. Having paid no price for their act of aggression, the aggressor is emboldened to attack again.

In contrast to McCoy’s pacifism, Mr. Spock (Leonard Nimoy) and Mr. Stiles (Paul Comi) both want to attack the Romulans. Stiles tells Kirk: “We have to attack. If we don’t … they’ll report we saw their weapons and ran.” If the Enterprise does not respond, the Romulans will send more ships and destroy more Earth Outpost Stations. Spock says, “Weakness is something we dare not show.” After considering the viewpoints of Spock and McCoy, Kirk attacks the Romulan Bird of Prey and destroys it. The Romulans pay a high price for their act of aggression—the loss of their flagship—which dissuades them from attacking again. Kirk’s proportional response does not lead to war. On the contrary, it restores the balance of power between Earth and the Romulans and ends the conflict.

Taking military action after an unprovoked attack is a deterrent against future attacks, and the stronger the response, the greater the deterrent. “Balance of Terror” reminds us that to stop an aggressor from attacking again, there will often be a cost. In the battle between the Enterprise and the Romulans, Robert Tomlinson (Stephen Mines) is killed. Kirk comforts the grieving widow by telling her, “There was a reason.” Tomlinson died in the line of duty for a noble reason: to prevent future attacks by the Romulans. This is the goal of any just military action: to save the lives of innocent civilians, not only in the present, but also in the future. If Kirk hadn’t destroyed the Romulan ship, the Romulans would have sent more ships and started a war.

Notes

1. Lionel Beehner, “Israel and the Doctrine of Proportionality,” Council on Foreign Relations, July 13, 2006, http://www.cfr.org/israel/israel-doctrine-proportionality/p11115#p0