There are actions we widely believe are and should be illegal: slavery, rape, genocide. War is no longer on the list. It has become a well-kept secret that war is illegal, and a minority view that it should be illegal. I believe we have something to learn from an earlier period in our history, a period in which a law was created that made war illegal for the first time, a law that has been forgotten but is still on the books.

In 1927-1928 a hot-tempered Republican from Minnesota named Frank who privately cursed pacifists managed to persuade nearly every country on earth to ban war. He had been moved to do so, against his will, by a global demand for peace and a U.S. partnership with France created through illegal diplomacy by peace activists. The driving force in achieving this historic breakthrough was a remarkably unified, strategic, and relentless U.S. peace movement with its strongest support in the Midwest; its strongest leaders professors, lawyers, and university presidents; its voices in Washington, D.C., those of Republican senators from Idaho and Kansas; its views welcomed and promoted by newspapers, churches, and women’s groups all over the country; and its determination unaltered by a decade of defeats and divisions.

The movement depended in large part on the new political power of female voters. The effort might have failed had Charles Lindbergh not flown an airplane across an ocean, or Henry Cabot Lodge not died, or had other efforts toward peace and disarmament not been dismal failures. But public pressure made this step, or something like it, almost inevitable. And when it succeeded — although the outlawing of war was never fully implemented in accordance with the plans of its visionaries — much of the world believed war had been made illegal. Wars were, in fact, halted and prevented. And when, nonetheless, wars continued and a second world war engulfed the globe, that catastrophe was followed by the trials of men accused of the brand new crime of making war, as well as by global adoption of the United Nations Charter, a document owing much to its prewar predecessor while still falling short of the ideals of what in the 1920s was called the Outlawry movement.

“Last night I had the strangest dream I’d ever dreamed before,” wrote Ed McCurdy in 1950 in what became a popular folk song. “I dreamed the world had all agreed to put an end to war. I dreamed I saw a mighty room, and the room was filled with men. And the paper they were signing said they’d never fight again.” But that scene had already happened in reality on August 27, 1928, in Paris, France. The treaty that was signed that day, the Kellogg-Briand Pact, was subsequently ratified by the United States Senate in a vote of 85 to 1 and remains on the books (and on the U.S. State Department’s website) to this day as part of what Article VI of the U.S. Constitution calls “the supreme Law of the Land.”

Frank Kellogg, the U.S. Secretary of State who made this treaty happen, was awarded a Nobel Peace Prize and saw his public reputation soar — so much so that the United States named a ship after him, one of the “Liberty ships” that carried war supplies to Europe during World War II. Kellogg was dead at the time. So, many believed, were prospects for world peace. But the Kellogg-Briand Pact and its renunciation of war as an instrument of national policy is something we might want to revive. This treaty gathered the adherence of the world’s nations swiftly and publicly, driven by fervent public demand. We might think about how public opinion of that sort might be created anew, what insights it possessed that have yet to be realized, and what systems of communication, education, and elections would allow the public again to influence government policy, as the ongoing campaign to eliminate war — understood by its originators to be an undertaking of generations — continues to develop.

We might begin by remembering what the Kellogg-Briand Pact is and where it came from. Perhaps, in between celebrating Veterans Day, Memorial Day, Yellow Ribbon Day, Patriots Day, Independence Day, Flag Day, Pearl Harbor Remembrance Day, and the Iraq-Afghanistan Wars Day legislated by Congress in 2011, not to mention the militaristic festival that bombards us every September 11th, we could squeeze in a day marking a step toward peace. I propose we do so every August 27^th. Perhaps a national focus for Kellogg-Briand Day might be on an event in the National Cathedral in Washington, D.C., (if it safely reopens following the recent earthquake) where the inscription below the Kellogg Window gives Kellogg, who is buried there, credit for having “sought equity and peace among the nations of the world.” Other days could be developed into peace celebrations as well, including the International Day of Peace on September 21^st, Martin Luther King Jr. Day every third Monday in January, and Mothers Day on the second Sunday in May.

We would be celebrating a step toward peace, not its achievement. We celebrate steps taken toward establishing civil rights, despite that remaining a work in progress. By marking partial achievements we help build the momentum that will achieve more. We also, of course, respect and celebrate the ancient establishment of laws banning murder and theft, although murder and theft are still with us. The earliest laws making war into a crime, something it had not been before, are just as significant and will long be remembered if the movement for the Outlawry of war succeeds. If it does not, and if the nuclear proliferation, economic exploitation, and environmental degradation that come with our wars continue, then before long there may be nobody remembering anything at all.

Another way to revive a treaty that in fact remains law would, of course, be to begin complying with it. When lawyers, politicians, and judges want to bestow human rights on corporations, they do so largely on the basis of a court reporter’s note added to, but not actually part of, a Supreme Court ruling from over a century back. When the Department of Justice wants to “legalize” torture or, for that matter, war, it reaches back to a twisted reading of one of the Federalist Papers or a court decision from some long forgotten era. If anyone in power today favored peace, there would be every justification for recalling and making use of the Kellogg-Briand Pact. It is actually law. And it is far more recent law than the U.S. Constitution itself, which our elected officials still claim, mostly unconvincingly, to support. The Pact, excluding formalities and procedural matters, reads in full,

The High Contracting Parties solemly [sic] declare in the names of their respective peoples that they condemn recourse to war for the solution of international controversies, and renounce it, as an instrument of national policy in their relations with one another.

The High Contracting Parties agree that the settlement or solution of all disputes or conflicts of whatever nature or of whatever origin they may be, which may arise among them, shall never be sought except by pacific means.

The French Foreign Minister Aristide Briand, whose initiative had led to the Pact and whose previous work for peace had already earned him a Nobel Peace Prize, remarked at the signing ceremony,

For the first time, on a scale as absolute as it is vast, a treaty has been truly devoted to the very establishment of peace, and has laid down laws that are new and free from all political considerations. Such a treaty means a beginning and not an end. . . . [S]elfish and willful war which has been regarded from of old as springing from divine right, and has remained in international ethics as an attribute of sovereignty, has been at last deprived by law of what constituted its most serious danger, its legitimacy. For the future, branded with illegality, it is by mutual accord truly and regularly outlawed so that a culprit must incur the unconditional condemnation and probably the hostility of all his co-signatories.