“Day of the Dove” was written by accomplished science fiction writer Jerome Bixby, who wrote several other episodes including the classic “Mirror, Mirror” in the second season. It aired for the first time on November 1, 1968 (between Halloween and the Catholic “All Soul’s Day” or Day of the Dead.)

1968 was a year of death and violence, and deep emotional divisions. The war in Vietnam was raging, both with U.S. bombing in both South and North Vietnam, and the ground war in South Vietnam. In a two-week period in May, more than 1,100 U.S. soldiers were killed.

In early April, Martin Luther King was assassinated, setting off destructive rioting in many U.S. cities. Troops had to be sent to Chicago, Boston, Detroit, Washington and Baltimore.

There were student revolts in the U.S. and Europe. In early June, Robert Kennedy was assassinated, just as he appeared on his way to the Democratic nomination for President on an anti-war platform. There were massive demonstrations in Chicago at the Democratic convention that summer, with nightly violence broadcast coast to coast, caused by what a presidential commission would later call “a police riot.”

The war had divided the country in many ways and in the deepest ways probably since the Civil War, for longstanding alliances and friendships were fractured and families were split—brother against brother, husbands against wives, and most of all, parents against children.

The 60s were a time of great change happening very fast: in everything from sexual mores and relationships, to racial and gender stereotypes. The truthfulness as well as the judgment of leaders was called into question, as well as the rightness of actions and goals. Was war necessary to achieve these goals, and were they worthy goals in the first place?

So much of what nearly everyone had simply accepted as good and true was questioned. Were all our comfortable homes, vibrant industries and wonderful consumer products not so innocent after all—were they the result of processes that were poisoning the air and water, and destroying the planet? Was our prosperity based in part on exploiting others? These questions had not been raised in so many American homes before. This caused great distress, terrible tensions and intimate conflict.

At the same time, the U.S. and Soviet Union were separately sending manned spacecraft into orbit. In the month before this episode aired, Apollo 7 hosted the first live television broadcast from space, during an 11 day mission orbiting the earth 163 times. And during a four-day mission, a manned Soviet craft practiced approach maneuvers with an unmanned craft, a prelude to docking.

People were seeing what the future could be, and they were seeing the present in a kind of self-destruction, threatening that future.

For many, space exploration represented what science and rational thinking could do. On the other hand (some believed) the violence that seemed to have the world in its grip seemed evidence of the damage fiery emotions could cause. This way of looking at what was happening in the late 60s was part of the appeal of Mr. Spock.

Sock represented “logic,” which meant not only science, but what philosophers had called “reason.” The Founding Fathers considered themselves men of reason; they thought of the Declaration of Independence and the Bill of Rights as reasoned and reasonable documents, that brought principles to bear on evidence; that brought the logic of those principles to bear on current situations. Those principles were themselves a combination of ideals and pragmatism, a set of logical rules based at least in part on hopes and aspirations.

At the same time, those who were against the Vietnam war claimed that the so-called logic of its proponents was too narrow. It left out too many facts that called these rigid conclusions into question. And it left out human consequences and their importance, which transcended the logic of numbers and had devastating effects on human lives and the physical environment. In order to gauge the importance of lives, and the suffering caused by violence and warfare, perhaps took feelings: the exercise of empathy. But they did not see this as irrational (though many pro-war advocates did.) They saw this as reason---as factoring in human suffering and destruction as well as history, geopolitical realities and the quantitative measurements of weapons and warfare.

Only with the candidacy of Eugene McCarthy and Robert Kennedy in the spring 1968 primaries did opposition to the war gain some legitimacy, and even a lot of that was withdrawn due to later violence. Many people continued to believe that anti-war demonstrators were traitors to their country. They reacted with violent emotion, and at times with real violence.

One of those actively opposing the war was Leonard Nimoy, who was active in support of Eugene McCarthy, as well as for civil rights, civil liberties and social justice causes. In 1968, Mr. Spock met Dr. Spock at a political event. (Dr. Benjamin Spock, world famous as the baby doctor, but also a peace activist who’d been arrested protesting the draft. As Nimoy recounts in his books, he introduced himself as the man who played Spock. Dr. Spock said only, “I know. Have you been indicted yet?”)

Though Star Trek stories did not always carry a blatant anti-war message, Bixby admitted this was his intent with “Day of the Dove” (as the title itself gives away. It was during Vietnam that the terms, “hawks” for pro-war and “doves” for pro-peace, became well known. I believe the terms originated in a magazine article about the White House deliberations during the Cuban Missile Crisis in 1962.)