Who will clap when? That’s the annual political parlor game during President Obama’s State of the Union speech — the president’s party cheering on its leader and the opposition rarely clapping unless it’s about supporting our troops or “God bless America.”

Pope Francis’s address to a joint meeting of Congress adds another level of intrigue for observers of applause: three Catholics of very different molds will be standing on the dais. Behind the pope will be Speaker John A. Boehner and Vice President Biden, political opponents and lifelong Catholics.

Boehner and Biden often shower praise on the pontiff.

“Pope Francis has breathed new life into what I believe is the central mission of our faith: Catholic social doctrine,” Biden said. Boehner, who extended the original invitation, said, “The visit of Pope Francis to the U.S. Capitol is a historic moment for the country.”

But will both leaders sustain their praise when Francis brings his frank political and economic analysis to Congress? He will probably bring tough criticism of central planks in both parties’ platforms.

Will they stand? Will they clap? One certainty: We’re unlikely to see a Rep. Joe Wilson-type moment of anyone yelling “You lie!” at Pope Francis. Beyond that, there are few certainties and at least six potentially awkward issues that could be raised.

Abortion

Pope Francis recently encouraged women to seek forgiveness for having an abortion, an issue that has flared up again in recent months. Boehner’s and his fellow Republicans’ efforts to defund Planned Parenthood after a series of videos released by anti-abortion activists brings abortion to the center of political attention.

Cardinal Sean O’Malley responded to the videos by first quoting Francis’s reasoning on why people abort pregnancies, “[the] widespread mentality of profit, the throwaway culture, which has today enslaved the hearts and minds of so many,” before going on to call abortion “a direct attack on human life in its most vulnerable condition.” Democrats in the Senate have blocked attempts to stop government funding of Planned Parenthood.

The pontiff urged lawmakers at a joint meeting of Congress to balance concern for those living in poverty with protection from environmental deterioration, which he said was "caused by human activity." (AP)

Climate change

Francis’s Papal Encyclical “Laudato si” can best be described as a 184-page call to arms on climate change. Francis pulls few punches and takes direct aim at the United States, writing, “Those who possess more resources and economic or political power seem mostly to be concerned with masking the problems or concealing their symptoms.” The pope calls on the United States and other developed countries “to help pay this debt by significantly limiting their consumption of nonrenewable energy and by assisting poorer countries to support policies and programs of sustainable development.”

His visit to the United States also comes in advance of the United Nations Climate Change Conference in Paris this December, where world leaders will seek to finalize the first legally binding treaty on climate. Francis will probably call for the strongest possible agreement and U.S. leadership in Paris. Expect a lot of cheering from Biden, and perhaps less enthusiasm from the speaker. Boehner told reporters earlier this year, “I’ll let the scientists debate the sources in their opinion of that change.”

Iranian nuclear deal

Boehner promised his colleagues and supporters to “”do everything possible to stop” the Iranian nuclear deal. Perhaps he should have added, except disinviting the pope to address Congress? Pope Francis has given his strong seal of approval to the deal, calling it “a definitive step toward a more secure and fraternal world” during Easter Mass in St. Peter’s Square. Policy differences don’t get much more clear-cut than this divide.

Same-sex marriage

Adding another layer of political intrigue to the address, Biden is considering a run for the presidency. He’ll reportedly make the case that his early support for same-sex marriage helped push President Obama to the same position and preceded Hillary Clinton’s embrace.

Francis drew attention when he told a group of reporters two years ago, “If someone is gay and searches for the Lord and has goodwill, who am I to judge?” Interpreted as a change in tone for the Catholic Church, the social teaching Biden praises generally hasn’t changed specifically on marriage.

Biden hailed the Supreme Court’s recent decision on same-sex marriage, while the U.S. Conference of Catholic Bishops declared, “It is profoundly immoral and unjust for the government to declare that two people of the same sex can constitute a marriage.” Boehner led the charge to defend the Defense of Marriage Act when the president and attorney general refused.

While addressing Congress, Pope Francis says America should not be fearful of immigrants because, "most of us were once foreigners." (AP)

Immigration

The pope seems to always be on the move, but his first trip took him to Lampedusa, Italy, in 2013. There he drew attention to the plight of migrants worldwide and lamented the “the globalization of indifference.”

Following the pope’s example, Cardinal Sean O’Malley and eight Catholic Bishops  celebrated Mass on the U.S.-Mexico border in 2014 calling for broad immigration reform and respect for immigrants. Not long after the border Mass, immigration changes stalled in the House of Representatives as a wing of the Republican Party put pressure on Boehner.

U.S.-Cuba relations

While diplomats in Washington and Havana have squabbled for decades, the pope helped facilitate the deal that began to normalize relations. Cuban President Raúl Castro even said after the agreement, “If the pope continues this way, I will go back to praying and go back to the church.” Pope Francis visited Cuba directly before coming to the United States, which will probably only increase tensions on this issue. Boehner pilloried the deal, decrying “another in a long line of mindless concessions to a dictatorship that brutalizes its people and schemes with our enemies.”

Ahead of the visit, Boehner’s Democratic predecessor and fellow Catholic, Rep. Nancy Pelosi, the House minority leader, indicated her excitement: “Pope Francis has renewed the faith of Catholics worldwide and inspired a new generation of people, regardless of their religious affiliation, to be instruments of peace.” But will excitement give way to grappling with the hard messages that will confront leaders of both political parties?

Will Boehner and Biden openly disagree with the pope’s politics, like their fellow Catholic Jeb Bush, a GOP presidential candidate? On the campaign trail recently, Bush argued, ““I think religion ought to be about making us better as people, less about things [that] end up getting into the political realm.” That will be a hard line to take for the two men seated directly behind Francis today.

It’s hard to imagine Francis bringing a cheery feel-good slap on the back to the United States. Boehner, Biden and Congress should expect surprises, and we at home can expect a host of awkward clapping.

Guthrie Graves-Fitzsimmons (@guthriegf) writes at the intersection of faith and public policy. From 2011 to 2015, he worked at the National Immigration Forum mobilizing Christians to advocate for the value of immigrants and immigration to America.

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