The shadow of Iraq hangs over the nuclear standoff between North Korea and the United States.

The U.S.-led invasion of Iraq drew condemnations from both St. John Paul II and then-Cardinal Joseph Ratzinger.

In a 2003 Zenit interview, the future Pope Benedict XVI rejected claims that the invasion fit Catholic criteria for a “just war.”

But he went further, questioning whether there can even be a just war anymore. “Given the new weapons that make possible destructions that go beyond the combatant groups, today we should be asking ourselves if it is still licit to admit the very existence of a ‘just war,’ ” he said.

Msgr. Stuart Swetland, a moral theologian and former naval officer, told Angelus News that the Church’s just-war teaching is only intelligible as an absolute last resort geared toward restoring a just peace and tranquil order.

Msgr. Swetland said the struggle against the Nazis in World War II meets this test, as do the 1991 liberation of Kuwait and military efforts to stop the ongoing genocide of Christians and Yazidis by ISIS.

The Church’s just-war tradition undergirds international law and restricts both the decision to go to war (“jus ad bellum”) and the decisions taken in war (“jus in bello”).

The principles outlined in the Catechism of the Catholic Church (no. 2309) state that a defensive war is permissible only when the enemy’s threat is “grave” and all other nonviolent options have been exhausted.

Even then, the Catechism says, “the use of arms must not produce evils and disorders graver than the evil to be eliminated.”

Nuclear weapons have no moral place in the just-war framework because of their devastating and long-term impact on civilian population centers, Msgr. Swetland said.

The U.S. strategy of deterrence raises further moral problems, he added. It forces U.S. military personnel to make a “conditional decision” to participate in mass murder should a nuclear launch order be given — an order the Catechism makes clear must be disobeyed.

Mary Ellen O’Connell, who has written a book about warfare since the 9/11 terror attacks, said negotiations with North Korean can work.

She pointed to the mid-1990s, when the U.S. convinced then President Kim Jong Il to give up his nuclear program in exchange for light nuclear reactors capable of generating power but not the materials for a nuclear weapon.

However, she recalled, President Clinton failed to secure funding for the agreement after Congress balked, and later blamed his failure on the Kim regime.

Today, she said, “the only way the North Korean crisis ends well is a negotiated settlement.”

See also related article by  Peter Jesserer Smith, Going nuclear - now an option?

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