Pope Francis gestures to journalists during a news conference on July 13, 2015, onboard a plane on his way back to Rome from Paraguay, the final stop of his South America tour. (AFP photo / Vincenzo Pintovincenzo Pinto/AFP/Getty Images)

This analysis is by Kevin Clarke, a senior editor and chief correspondent at America magazine.

To paraphrase a joke that circulates in Jesuit circles: Pope Francis is the best at humility. He proved it again on his plane ride home from South America when he frankly acknowledged that “it was an error of mine” not to have said more about the struggles of the world’s middle class. A sharply worded criticism of unfettered capitalism in Bolivia had been only his most recent denunciation of a throwaway economy and a demand for greater systemic attention to the continuing plight of the world’s poor.

During one of the off-the-papal-cuff news conferences that have become a hallmark of his pontificate, Pope Francis explained to reporters because the poor are at the “heart of the Gospel” they enjoy a preferential option for his attention.

But he also thanked a reporter for reminding him of his duty as well to advocate on behalf of the global middle class, and he assured that he would turn his attention to their concerns after proper Jesuitical due diligence of study and reflection.

While most may think a fellow like Francis could fall back on the purported–and largely misunderstood–infallibility of his office, this pontiff seems completely at ease with the fully human capacity to make a mistake and to accept corrections—even from as unlikely a source as a plane-load of reporters.

It was hardly his most significant apology that week, however. In the same speech in Bolivia, in fact, he followed up on a previous apology from Pope John Paul II to more humbly express regret for church transgressions against the native people of the new world.

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His remarks in Latin America preview what are likely to be the major concerns of his unprecedented address before Congress in September. Those whose hearts beat a little faster during bedtime stories of 19th century laissez faire capitalism should buckle up when Francis comes to Washington. “An unfettered pursuit of money rules,” he said in Bolivia, leading to a benighted planet, poisoned with the “dung of the devil.” Not exactly subtle. But sometimes Pope Francis has to play prophet and say the hard things that might awaken first world consciences.

This Latin American pope has had a front-seat view of the real world results of North America’s deification, as he puts it, of the free market, a ideological idolatry which reads mostly benignly in economic textbooks but which can produce ugly outcomes outside the classroom — ecological degradation, wage slavery, vast communal dislocation and commodity-market driven hunger.

Pope Francis, in keeping with a long history of Catholic social tradition, thinks there is a better way to order the world economy — one his immediate predecessors have more softly promoted. But his criticism of the current world order is not likely to go over well in a nation that remains smugly convinced of its exceptionalism and a claim of historical infallibility that would make any pontiff blush.

There will no doubt be ugly accusations thrown at Pope Francis when he presses his concern for creation, the global poor and soon apparently the world’s middle class in the United States. Some have already attempted to dismiss his critique of capitalist excess as “socialism,” tapping into a paranoid thread in the North American psyche and intending to shut down thoughtful deliberation of the pope’s demanding message.

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But the pope is not a Marxist; he is not any sort of political revolutionary. He is, as he has said, foremost a sinner and a Christian. He has already acknowledged that the Catholic magisterium will itself not presume to prescribe specific socio-economic reforms toward the more just future he waits and hopes for. That will be work left up to the rest of us.

Pope Francis is not interested in changing political or economic systems, but in changing hearts, in acts of personal conversion that can lead to social transformation. He is not calling just for better mitigation of the suffering of the poor or reforms of global markets, but change which is redemptive for everyone.

His is a revolution of conscience that “saves” the tiny percentage of the world’s rich from the spiritual morass of materialism as much as it rescues billions around the world from the blunt deprivations of poverty.

He has come not to profess socialism, but to proclaim a social moral principle: that a just economic order—one well within our reach—is one that serves people and protects the earth, not one that exhausts people and creation as disposable economic inputs. That will not be a popular message in the United States, but it is one the world’s leading capitalist power—and consumer of the earth’s vast bounty—needs to hear.

Kevin Clarke is author of “Oscar Romero: Love Must Win Out” (Liturgical Press). He is on Twitter at @clarkeatamerica.

(This piece has been updated.)

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