An explosive fight

WORLD

MARCH 2017 WAS AN EXHILARATING TIME FOR Beatrice Fihn. The executive director of the International Campaign to Abolish Nuclear Weapons (ICAN) was at the U.N. in New York City for talks with more than 120 countries to negotiate a treaty on banning nuclear weapons. One moment still stands out: Nikki Haley, then U.S. ambassador to the U.N., and a group of diplomats from several NATO countries held a press conference outside the General Assembly to protest the talks.

“It was such a hilarious role reversal,” Fihn tells me when we meet for lunch in New York this fall, referring to all the times nuclear-disarmament activists have been outside the corridors of power. “Now, we were in the driver’s seat.”

Fihn, 40, has been trying to shift these dynamics ever since she took the helm of the Geneva-based ICAN nearly a decade ago. In 2017, the charismatic Swedish lawyer was thrust into the spotlight when she accepted the Nobel Peace Prize for ICAN’s work to draw attention to the humanitarian consequences of nuclear weapons and its efforts to establish the Treaty on the Prohibition of Nuclear Weapons (TPNW). Now ratified by 68 countries, mostly in the Global South, the ban treaty entered into force in January 2021—the first international legally binding agreement to ban nuclear weapons and activities like testing and development.

However, since then, Fihn feels like things have backslid. Vladimir Putin’s threats have reminded the world that nuclear war is not just a Cold War–era concern. In a March poll, 7 in 10 Americans said Russia’s invasion of Ukraine increased the possibility of nuclear weapons being used anywhere. “There’s so much happening and it’s hard to keep up—a lot of anxiety and awfulness,” Fihn says. Growing great-power competition—from Kim Jong Un’s nuclear tests to China’s expanding arsenal—raises the stakes for Western democracies, she argues. “Nuclear weapons make us vulnerable to dictators that do not answer to their people.”

Though Fihn announced in November that she would step down as ICAN’s executive director at the end of January, she plans to remain involved and is optimistic about this moment, pointing to progress made after crises in the 1960s and 1980s when the world came to the brink of nuclear war. “People are talking about nuclear weapons more than they have since the ’80s. We have to use this to build a bigger movement—to double or triple in size—so we can set the stage for w