Even as the United States bombed Vietnam and the Red Army quashed an uprising in Czechoslovakia, there was a place where citizens from the two cold-war superpowers could meet: the CERN cafeteria.To this day, the same spot at Europe’s particle-physics laboratory near Geneva, Switzerland, is a rare venue for Pakistani and Indian physicists to have a coffee, or for engineers from Israel and Iran to share ideas — no doubt fuelled by the huge lunches and inspiring views.

There is no better cure for cross-border acrimony than meeting someone from the other country and realizing that they are not so different from yourself. And major science facilities, whose inhabitants already share many beliefs, such as in openness and the scientific method, are natural places to kindle such mutual understanding.

What a chance, then, for SESAME. Synchrotron-light for Experimental Science and Applications in the Middle East is a venture that brings together Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, the Palestinian Authority and Turkey, to build the region’s first synchrotron-light facility near Amman in Jordan. Proposed in 1997, modelled on CERN and created under the auspices of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in 2002, the remarkable collaboration is now set to open.

SESAME has struggled at every turn. Several member states have made only partial payments, and its opening has been delayed by more than five years owing to financial difficulties. Other hurdles were less predictable: 2009 and 2010 saw Iranian council members assassinated, and in 2013, the facility’s roof fell in after unprecedented snowfall.

But SESAME has also ridden on a wave of generosity and perseverance. Its director and various advisers contribute their time for free. Facilities in Germany, France, the United Kingdom, Sweden, Spain and Switzerland have donated crucial parts of the machine, and Jordan, which provided land for the site at no cost, has continued to cough up funding, even as the neighbouring Syrian war has brought huge numbers of refugees across its borders.

To get this far is a terrific success. But when it opens next year, the facility will have just two beamlines, rather than a planned four, and will be without an administration building, dormitory, major library, auditorium or visitor centre. Nor, sadly, will SESAME have its hub of scientific life, a cafeteria. Experimental equipment takes priority, but in a facility where time is so precious that researchers allotted 24 hours of beam time barely sleep, some worry that, with nowhere to grab a coffee and a seat, scientists from conflicting countries may pass like ships in the night.

A group from the Sharing Knowledge Foundation in Geneva is trying to raise €30,000 (US$32,000) through public donations by the end of this year towards creating a SESAME cafeteria. But funds for both the cafe and the science could also come from another source, which has been conspicuously lacking over the years: the United States.

A Congress ruling in 2011 cut funding to UNESCO, after the organization formally recognized Palestine as a member state. This is a public-relations difficulty for SESAME, even though there should be no official block because it is independent from UNESCO. A bigger question could be whether the incoming US president meddles with the Iran nuclear deal, which could restore sanctions.

Still, brokering peace in the Middle East is something that Donald Trump said on the campaign trail he’d “really like to do”. For less than the cost of a return flight to Tel Aviv on Air Force One, his administration could help SESAME to develop from a bare-bones scientific laboratory into a true beacon of peace and cooperation.