Sen. Bernie Sanders’s overnight trip to the Vatican last week was parsed mostly as a campaign tactic — whether this was a wise use of time with the New York primary approaching. Sanders’s supporters relished the contrast with Hillary Clinton. While the Vermont senator went to the Vatican and met with Pope Francis, Clinton traveled to California for two fundraisers with George Clooney, including a Friday night soiree asking a startling $353,400 contribution per couple to make it to the head table with Clinton.

For the most part, however, the substance got lost. Sanders went to the Vatican to speak at a small gathering of world figures convened by the prestigious Pontifical Academy of Social Sciences to commemorate the 25th anniversary of Centesimus Annus, the encyclical released by Pope John Paul II soon after the breakup of the Soviet Union. He used the occasion to provide a moral grounding for his political appeal.

In his remarks, Sanders located Centesimus Annus in a line of papal teaching that can be traced back to the dawn of the Industrial Age, with Pope Leo XIII’s encyclical, Rerum Novarum, issued in 1891 and forward to Francis’s stirring Laudato Si’, issued last year.

Sanders summarizes the essence of Centesimus Annus (issued for the 100th anniversary of Rerum Novarum) as the belief that while a market economy can be beneficial for productivity and economic freedom, the pursuit of profit cannot be an end in itself. John Paul II called on the state and society to provide “an adequate wage level for maintaining families,” arguing that unions are central to this mission. Profit that is the result of “illicit exploitation, speculation and breaking of solidarity among working people ... has no justification and represents an abuse in the sight of God and man.”

Twenty-five years after this encyclical, Sanders argues, we have failed to heed its warnings. “Speculation, illicit financial flows, environmental destruction and the weakening of the right of workers” are far more severe than they were a quarter century ago.

Now we witness an economy not aimed at the common good, but operated for the very few, as “the working class, the young and the poor fall further and further behind.” And the wealthy few reap the returns of the campaign contributions in the form of “special tax privileges, unbalanced trade agreements that favor investors over workers.”

This threatens not only our economy and democracy but also, Sanders argues, the very soul of our nation as the public loses faith in political and social institutions. He quoted Francis’s indictment from World Environment 2013: “Man is not in charge today; money is in charge; money rules.”

Francis calls this the “Globalization of Indifference.” Quoting from the encyclical, Sanders read: “We end up being incapable of feeling compassion at the outcry of the poor, weeping for other people’s pain, and feeling a need to help them, as though all this were someone else’s responsibility and not our own.”

And Sanders added, on Wall Street, financial fraud has become “the new business model. Top bankers have shown no shame for their bad behavior, and have made no apologies to the public.” The fines levied on their banks were just “another cost of doing business,” while their own fortunes went untouched.

Sanders made one last point to the gathering: This was not inevitable, that it could be changed. “I am told time and time again,” he said, “that we should be ‘practical . . . that a truly moral economy is beyond our reach.” But the consistent moral teaching of the church demands better. Francis himself, Sanders noted, is “surely the world’s best demonstration against such a surrender to despair and cynicism.”

For Sanders, the “hope and sense of possibility” comes from America’s young people. “Our youth are no longer satisfied with corrupt and broken politics and an economy of stark inequality and injustice. They are not satisfied with the destruction of our environment . . . They are calling out for a return to fairness, for an economy that defends the common good.”

We are rich enough, Sanders concludes, “to meet our needs and to protect the planet.” Our challenge is not mainly technological or financial. “Our challenge is mostly a moral one, to redirect our efforts and vision to the common good.”

As his brief remarks at the Vatican demonstrated, Sanders’s platform is much more than a poll-driven assembly of popular ideas; he is moved by a moral indictment of what we have become, and the faith that we are better than that. He has been sounding these notes his entire life. The grueling 24-hour trip to the Vatican will likely have little impact in the New York primary. But it did provide Sanders with the setting to reflect and to speak on the moral challenges we face. Few candidates would spend the time and energy. He could not pass it up.

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