On February 10, 2016, Peace Action—the largest peace organization in the United States—announced its endorsement of Bernie Sanders for the Democratic nomination for President.

Peace Action is the descendant of two other mass U.S. peace organizations: the National Committee for a Sane Nuclear Policy (SANE) and the Nuclear Weapons Freeze Campaign (the Freeze). SANE was founded in 1957 with the goal of ending nuclear weapons testing. Soon, though, it broadened its agenda to include opposing the Vietnam War and other overseas military intervention, reducing military spending, and backing nuclear disarmament treaties, as well as supporting economic conversion from military to civilian production. Among SANE’s early supporters were Eleanor Roosevelt, Martin Luther King, Jr., Walter Reuther, and Dr. Benjamin Spock. The Freeze, initiated by Randy Forsberg, appeared in the late 1970s and reached a peak in the first half of the 1980s, when it led a widespread campaign to halt the Reagan administration’s dramatic nuclear weapons buildup and the dangerous slide toward nuclear war. With much in common, SANE and the Freeze merged in 1987 to form Peace Action. Like its predecessors, Peace Action devoted its efforts to building a more peaceful world.

Although the three peace organizations rarely endorsed Presidential candidates, they did so on occasion. Appalled by the Vietnam War, SANE backed the peace campaigns of Eugene McCarthy in 1968 and George McGovern in 1972. In 1984, challenging the Reagan administration’s bellicose approach to international affairs, SANE and the Freeze endorsed Walter Mondale. Then, in 1992, fed up with twelve years of Republican hawkishness, the newly-combined organization threw its support behind Bill Clinton.

In its statement endorsing Bernie Sanders, Peace Action praised his opposition to both Iraq wars, support of legislation to reduce spending on nuclear weapons, strong backing of the Iran agreement, votes to curb military spending, and championing of diplomacy over war. According to Kevin Martin, the executive director of the peace organization, Sanders “best represents the values that Peace Action and its 200,000 supporters have espoused.” And, in fact, before Peace Action’s board of directors voted overwhelmingly to have the organization’s Peace PAC back the Sanders campaign, an online poll of Peace Action’s members revealed support for endorsement by 85 percent of the respondents.

This enthusiasm for Sanders among peace activists reflects other aspects of his record, as well. The U.S. Senator from Vermont has opposed NATO expansion into Eastern Europe, favored normalization of relations with Iran, and decried the Israeli attacks on Gaza in 2014 as “disproportionate” and “completely unacceptable.” When it comes to the war in Syria, he has opposed the establishment of a “no-fly zone” and the use of American ground troops. In a July 2015 interview, Sanders explained that, although he is not a pacifist, he believes that “war is the very, very, very last option.”