Forty years ago, Iranian students took 66 Americans hostage at the U.S. Embassy in Tehran, launching the hostage crisis that would grip the United States for 444 days. As chants of “Death to America” consumed the new Islamic republic, the United States found an unlikely ally in navigating the tumultuous political changes and securing the release of the first batch of hostages on Thanksgiving Day, Nov. 20, 1979: the Palestine Liberation Organization.

The PLO hoped its efforts to secure the release of these 13 hostages would open a conversation with the United States in the broader Arab-Israeli arena. But it would take almost another decade, a bloody Lebanese civil war, a PLO exile in Tunisia and a total PLO acceptance of U.S. requirements before the United States finally opened direct communications with the Palestinian leadership, in 1988. Those contacts enabled the Israeli-Palestinian peace process of the 1990s. That controversial and hard-fought diplomatic ground, however, is under threat from the Trump administration.

When the Iranian revolution broke out in 1979, the Carter administration had just finalized a peace treaty between Israel and Egypt and was working toward some form of Palestinian solution. While more sympathetic toward the Palestinians than his predecessors, President Jimmy Carter refused to talk to the PLO directly. The group was considered too radical because of its use of violence, its refusal to recognize Israel and its unwillingness to accept U.N. Security Council Resolution 242, which was the foundation for the “land for peace” formula. Moreover, the United States was also bound by a secret pledge to Israel that there could be no negotiations with the PLO until the organization recognized Israel’s right to exist.

While Carter spent time and energy trying out creative ways of establishing contacts with the PLO during his first year in office, the divide was too deep. However, when the Americans were taken hostage in Iran on Nov. 4, 1979, the Carter administration quickly reached out to the PLO in Lebanon, hoping the organization could act as a go-between to get Iran to release the hostages.

As a revolutionary movement with a Muslim leader, the PLO was seemingly well placed to negotiate with Ayatollah Ruhollah Khomeini in Iran. The PLO’s credentials were boosted by the fact that the PLO had provided the ayatollah with bodyguards during his exile in Paris and that, before the revolution, it had trained Iranian revolutionaries in Lebanon. After the revolution, the PLO established a formal presence in Iran when it took over the building that had once housed the Israeli Embassy in Tehran.

The PLO response to U.S. requests was positive. It was in no position to make demands, so it sent a delegation to Tehran to negotiate without asking for any quid pro quo. It hoped, but could not demand, that if it succeeded in securing the release of American hostages the U.S. administration would be so grateful that it would open direct political contact with the PLO leadership. The PLO had, by this point, realized the only path to a negotiated agreement with Israel passed through Washington.

But the PLO had less pull with the Iranian regime than it expected. The Iranian regime was undergoing a radicalization process, and the PLO was out of step with developments in the country. Furthermore, the PLO had built its relationship with Iranian revolutionaries before the revolution. Back then, it had been the stronger of the two nonstate groups. After the revolution, on the other hand, the PLO remained a nonstate movement while the Iranian revolutionaries commanded a state. The power dynamics shifted, and there were limits on what demands the PLO could make. It certainly did not help that it made its request on behalf of the United States.

Despite this, the PLO persuaded Iran to release an initial 13 U.S. hostages, all of whom were either women or African American men. Nicknamed the “Ayatollah’s version of ‘affirmative action’” by a U.S. negotiation consultant, the release was promoted by Iran as an anti-imperialist decision. Over the previous decade, the black liberation movement had gained international traction in its critique of American racial policy at home and abroad. Khomeini gave support to this idea when he released those hostages, noting Islam’s respect for women and saying that American blacks were an oppressed population. But the architect of the idea was the PLO.

After the release of those 13, the negotiations deteriorated. The PLO again tried to influence Khomeini in January 1980, but with no success. In April 1980, the Carter administration attempted a high-risk military operation to get the hostages out of Iran. The mission was a tragic failure, and eight Americans died at the landing sight, called Desert One. According to a 1988 article in The Washington Post, the PLO then managed to secure the release of the bodies. This claim is also made in Kai Bird’s 2014 book, “The Good Spy.” Unfortunately, the claim has been impossible to verify.

But CIA documents reveal that as late as September 1980, almost a year into the hostage crisis, the PLO was still listed as one of the central third-party actors that could help negotiate the release of the hostages. In the end, it was not the PLO that provided the final breakthrough in the hostage negotiations, but not for lack of trying.

Throughout the hostage crisis, both the PLO and the U.S. administration walked a political tightrope. On one hand, the PLO was aggrieved by the Camp David Accords and the Egyptian-Israeli negotiations, which had completely sidelined it, and did not want to be perceived as siding with the United States against Iran. On the other hand, it had concluded that establishing direct contacts with the United States was necessary to gain traction in a peace process from which it had been excluded. The United States, for its part, was desperate to get the hostages released but did not want to be seen as getting too close to the PLO.

Both the PLO and leading members of Carter’s foreign policy team seemed to conclude that closer cooperation between the two would be possible after the 1980 U.S. election. When Ronald Reagan won, PLO leader Yasser Arafat passed a message to the Americans suggesting they continue the contacts they had established through the hostage negotiations. These were false hopes. The incoming Reagan administration was far more hard line when it came to the Middle East. While the Reagan administration famously helped evacuate the PLO from Lebanon in 1982, it did not open political talks with the PLO until 1988, when the organization had succumbed to all U.S. demands.

The PLO role in the hostage crisis became a forgotten footnote in history because it complicates the story of the PLO as a natural enemy of the United States. President Trump has reinvigorated this idea of natural enmity by closing the doors to the PLO office in Washington. This move came as the final nail in the coffin of a peace process that has been deteriorating for years. This absolute break in communications means it would be difficult to rebuild even a modicum of trust.

The hostage crisis reveals the positive potential of negotiation and collaboration. The relationship with the PLO was never an easy one, but communication can produce concrete benefits, something the Trump administration sorely needs today.