This article was originally posted at Providence.

Testifying before Congress last week, Secretary of State John Kerry defended his role in brokering a cease fire in the Syrian civil war—a temporary “cessation of hostilities” that no one expects to produce a just outcome for the Syrian people. “If it doesn’t work, the potential is there that Syria will be utterly destroyed,” Mr. Kerry warned. “The fact is that we need to make certain that we are exploring and exhausting every option of diplomatic resolution.”

Exactly when, in the long annals of international diplomacy, has the determination to “exhaust” all the alternatives to the use of military force ever brought a genocidal regime to its knees? That fact is, never.

This is why the French ambassador to the United Nations called the cease fire “a smoke screen” that would allow Syria’s Bashar al-Assad “to crush the Syrian civilians and the opposition.” Yes, the French, under the socialist leadership of Francois Hollande—the French!—are more clear-eyed about the moral dynamic of the Syrian conflict than the United States under President Barack Obama.

Mr. Kerry and the White House pretend that Mr. Assad has even the slightest incentive to compromise with the Syrian rebels. Their entire diplomatic strategy—their discredited demand that “Assad must go”—is based on a fantasy. After six months of relentless Russian air strikes on U.S.-backed rebel forces, the Syrian regime has regained the military advantage. This will likely include control over the city of Aleppo, considered the rebel capital of the revolution. More militarily secure than he has been in months, Mr. Assad can dictate the terms of any agreement.

“Regardless of whether a ceasefire takes hold, any political settlement would reflect the current balance of power, which favors Mr. Assad,” Fawas A Gerges, professor of International Relations at the London School of Economics, told the BBC; “Far from the beginning of the end, the Syrian conflict has entered a new phase in which the Assad regime has momentum on the battlefield and the negotiating table.”

Mr. Assad can thank America’s complicity with Mr. Putin’s strategic intervention on behalf of the Syrian government: For months the administration downplayed or ignored Russia’s infusion of fighter jets, advanced weapons, and military advisors. Russia’s rising influence in the region, along with that of the Iranians—whose terrorist activities supporting Mr. Assad earned them a seat at the negotiating table—represent yet another foreign policy debacle for Mr. Obama and the United States.

Expect more to come. According to the United Nations, the Syrian military and the forces of the Islamic State have put at grave risk the lives of over 487,000 people caught in the crossfire and cut off from humanitarian assistance.  Mr. Kerry reportedly planned to have a “serious conversation” with the Russian foreign minister, Sergei Lavrov, about allowing humanitarian aid to reach them. But, like a muffin facing a machete, Mr. Kerry has been repeatedly outflanked by his Russian counterpart.

This brings us back to the Kerry principle of “exhausting every option of diplomatic resolution,” regardless of the human consequences. Where does this risible idea come from?

Among other places, it can be traced to an anti-nuclear weapons document produced by the U.S. Catholic bishops in the 1980s. Called “the Challenge of Peace,” their pastoral letter redefined the just war tradition to address the threat of nuclear war. Not only must military action be a last resort, they argued, but “all peaceful alternatives must have been exhausted.”

No one with lived memories of Cold War tensions can fault the bishops for wanting to avoid a nuclear holocaust. But their pacifist distortion of just war doctrine—which never included an exhaustive search for non-military means to check lawless aggression—has unwittingly aided the agents of barbarism. By prioritizing peace over justice, the Doctrine of Exhaustive Diplomacy has helped to dull the conscience toward the victims of violence. It has empowered the purveyors of genocide.

“None of us are under any illusions,” Mr. Obama claimed last week about the Syrian cease-fire agreement. “But history would judge us harshly if we did not do our part in at least trying to end this terrible conflict with diplomacy.”

In truth, U.S. policy has been rooted in a string of illusions—fallacies about America’s role in the world, about the nature of radical Islam, about the resilience of the forces of evil. Meanwhile, history’s judgment of Mr. Obama’s role in perpetuating these falsehoods, and deepening the human tragedy of this conflict, is already being written.

Joseph Loconte is an associate professor of history at the King’s College in New York City and the author of A Hobbit, a Wardrobe, and a Great War: How J.R.R. Tolkien and C.S. Lewis Rediscovered Faith, Friendship, and Heroism in the Cataclysm of 1914-1918.