On New Year’s Day, the North Korean leader Kim Jong Un claimed “a nuclear button is always on the desk in my office.” In this respect he is no different from any other commander of a nuclear power — though the “button” is actually a metaphor, and most heads of state would prefer to be known for keeping their finger a safe distance from it. Restraint is what makes them good stewards of nuclear weapons.

Except there is no such thing as a good threat of mass death and destruction. Pacifist Christians and nuclear abolitionists long have said this. Now so does the pope.

On Nov. 10, Pope Francis said of nuclear weapons: “The threat of their use, as well as their very possession, is to be firmly condemned.”

With these words, Francis moved the Catholic church toward a nonviolent ethic similar to that of Mennonites and other peace churches. (It was the second such instance in just a few weeks; in October he called for a revision of official church teaching on capital punishment — from allowing it in certain circumstances to complete rejection.)

When President Trump last year threatened to “totally destroy” North Korea, most critics of his overheated pronouncements still considered the United States a good owner of nuclear weapons and North Korea a bad one. But Francis made no such distinction. Nor did he counsel prudence and restraint. He simply set forth the full implications of the gospel of peace: Threatening millions with nuclear annihilation is an affront to morality, no less for a democracy than for a dictatorship. Potential button-pushers may bluster like Kim and Trump or, loath to speak lightly of nuclear war, let the arsenals speak for themselves. Loose talk multiplies the danger, yet fundamentally these are two versions of the same sin.

Even as threats to use atomic weapons escalated in 2017, moves to embrace the moral logic of peace gained traction. These shifts occurred on religious and political fronts.

In July, the United Nations passed the first legally binding international agreement to prohibit nuclear weapons. More than 50 countries have ratified the treaty, which sets a goal of abolition. The signatories do not expect the nine nuclear-armed powers to give up their arsenals any time soon, but they believe it is possible to turn public opinion against especially repugnant weapons — as has happened with chemical and biological arms, land mines and cluster bombs.

For its work on the treaty, the International Campaign to Abolish Nuclear Weapons, or ICAN, won the Nobel Peace Prize. Mennonite Central Committee had a connection to the award. It is a member of Project Ploughshares, which in turn is a member of ICAN. Cesar Jaramillo, executive director of Project Ploughshares, summed up the principle behind the abolition campaign: “There are no right hands for wrong weapons.”

Some hands are more wrong than others. While Trump and Kim traded taunts like petulant children (“I too have a nuclear button, but it is much bigger and more powerful,” Trump tweeted), Pope Francis and other Catholic officials set an example of visionary leadership. Rejection of nuclear weapons, a stance emerging among Catholics for years, now has the full support of a pope who speaks boldly for peace. As the U.S.-North Korean confrontation draws attention to the dangers that prevail while nuclear weapons exist, all nonviolent Christians must join to urge the peaceful resolution of conflict and the moral necessity of nuclear disarmament.