Every action has an opposite and equal reaction. It’s a law of the universe as we currently understand it. In a more general sense, every action has consequences, both positive and negative. A lot of ripples are going to be created when something as large as a nation or as blunt as military force throws a stone into a pond. McNamara urges us to remember that in order to do good, you may have to engage in evil.

Objectively, there is no greater evil than ending a human life. If one is religious, edicts against killing are found in every sacred text. If not, it’s a waste beyond measure to end a nearly cosmically impossible life.

Yet, the United States has certain values and certain responsibilities on the world stage. If the United Nations decides that genocide is occurring, it is our responsibility to stop it, with military force if necessary. If an ally is attacked, we are bound to protect them, with military force if necessary. If we are attacked, we must defend ourselves. A nation can do none of these things without engaging in evil.

The key is to minimize the evil as much as possible. World War II was a brutal, evil event. Millions died as the Allies grinded down the Axis war machine. Yet, it was certainly a lesser evil than allowing Hitler to control Europe and Tojo Asia. That said, the 100,000 Japanese civilians killed in Tokyo or the 24,000 in Dresden would probably disagree that its evil was minimized.

During the Vietnam War, protests against the Johnson Administration erupted throughout the nation. During one such protest, Norman Morrison, a Quaker, burned himself to death below Robert McNamara’s Pentagon office. Suicide is an evil, which Morrison must have known. However, if he could sway decision-makers to reconsider their policies, his self-immolation might bring about a greater good. Certainly, doing violence to oneself minimizes evil.

For his part, McNamara knew that violence is evil, but that he was exercising the legitimate authority of a democratically elected government. McNamara’s responsibilities as Secretary of Defense were clear: To ensure that the protests did not interfere with the operation of the government. As such, McNamara did not hesitate to use military force to guard the Pentagon. However, knowing human nature, McNamara refused to allow soldiers to load their rifles, foresight that was later validated by the Kent State Massacre. McNamara had a tough needle to thread, but he succeeded, at home at least, in minimizing the evil necessary to do his job.

This is an important lesson for any leader, or citizen in a democratic society, to remember. Death, especially unnecessary death, is to be avoided at all costs. However, we cannot allow ourselves to be paralyzed by the fear of committing evil in order to accomplish a greater good.

Jump to a lesson:
Introduction
Lesson 1: Empathize with Your Enemy
Lesson 2: Rationality Will Not Save Us
Lesson 3: There’s Something Beyond One’s Self
Lesson 4: Maximize Efficiency
Lesson 5: Proportionality Should Be a Guideline in War
Lesson 6: Get the Data
Lesson 7: Belief and Seeing Are Often Both Wrong
Lesson 8: Be Prepared to Re-examine Your Reasoning
Lesson 9: In Order To Do Good, You May Have To Engage in Evil
Lesson 10: Never Say Never
Lesson 11: You Can’t Change Human Nature
Conclusion