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U.N. Treaty Banning Nuclear Weapons Takes Effect, Without The U.S. And Other Powers

Activists in New York City show their support for the Treaty on the Prohibition of Nuclear Weapons, which took effect on Friday.
Erik McGregor
LightRocket via Getty Images
Activists in New York City show their support for the Treaty on the Prohibition of Nuclear Weapons, which took effect on Friday.

A U.N. treaty outlawing nuclear weapons went into effect on Friday, having been ratified by at least 50 countries. But the ban is largely symbolic: The U.S. and the world's other nuclear powers have not signed the treaty.

"For the first time in history, nuclear weapons are going to be illegal in international law," Elayne Whyte, Costa Rica's former U.N. ambassador who oversaw the treaty's creation, tells NPR's Geoff Brumfiel.

The ban prohibits countries from producing, testing, acquiring, possessing or stockpiling nuclear weapons. It also outlaws the transfer of the weapons and forbids signatories from allowing any nuclear explosive device to be stationed, installed or deployed in their territory.

The Treaty on the Prohibition of Nuclear Weapons was adopted in the summer of 2017, in hopes of bringing new momentum to the push to curb the deadliest armament in the world. But even then, it was seen more as a moral statement than an enforceable ban.

The treaty is a 96-page reminder to nuclear weapons states, Whyte said, that "they need to be moving forward" with disarmament.

"How did the international community deal with slavery, colonialism? Once you delegitimize that conduct, it completely has an impact on the policymaking process," she said.

The problem with the ban, global security analysts say, is that while dozens of countries say an outright prohibition is the best way to move ahead with disarmament, others — particularly those who possess nuclear weapons — disagree. The new treaty has also been seen as potentially undercutting the Nuclear Non-Proliferation Treaty that took effect in 1970. But its backers argue that nonproliferation has stagnated, decades after the U.S. and others agreed to that treaty.

"Supporters of the ban treaty say it serves to delegitimize nuclear weapons and reinforce global norms against use," the Nuclear Threat Initiative's Isabelle Williams wrote in 2017. She added later, "the new treaty is clear evidence of the worrying polarization of states — polarization driven, in part, by a perceived complacency among the nuclear-armed states and unwillingness to take serious steps to reduce the risks posed by nuclear weapons."

The treaty currently has 86 signatories. It has been ratified in 51 of those member states. Early signatories included the Holy See, New Zealand, Thailand and Austria. In the past year, countries such as Belize, Benin and Ireland have ratified or approved the treaty.

Nations that signed the treaty cite "the catastrophic humanitarian consequences that would result from any use of nuclear weapons," including by accident or miscalculation, saying those effects would transcend international borders.

Detonating a nuclear weapon, the signatories say, would "pose grave implications for human survival, the environment, socioeconomic development, the global economy, food security and the health of current and future generations, and have a disproportionate impact on women and girls, including as a result of ionizing radiation."

The treaty sets the goal of achieving a nuclear-weapon-free world, saying it would serve "both national and collective security interests." Any use of nuclear weapons, it adds, "would be contrary to the rules of international law" for armed conflict.

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Bill Chappell is a writer and editor on the News Desk in the heart of NPR's newsroom in Washington, D.C.