Editor's Note: (Michael D'Antonio is the author of the new book "Never Enough: Donald Trump and the Pursuit of Success" (St. Martin's Press). The opinions expressed in this commentary are his.)
(CNN) Donald Trump once told me, "I always loved to fight." But even those of us who know him and his fighting mentality have to marvel at his ability to find new battles. I mean really, Donald, you're going to argue with the Pope? About Christianity?
To be fair, from the Trumpian viewpoint, Pope Francis sort of started it. He decided to make a pilgrimage to Mexico and to include a visit to the border where Trump proposes to build a huge wall to keep people out. A champion of the poor and the suffering, Francis has visited slums all over the world and washed the feet of homeless men and women.
But for Trump, the trip to Mexico, where just about everyone is Catholic and about half the population lives in poverty, was a step too far.
"I think that the Pope is a very political person," Trump said in a TV interview last week.
He then wondered whether maybe Francis was a pawn of the Mexican government. "I don't think he understands the danger of the open border that we have with Mexico," said Trump. "I think Mexico got him to do it because they want to keep the border just the way it is. They're making a fortune, and we're losing."
Trump's pre-emptive strike, made before the Pope even left Rome, was a play for votes in South Carolina, where religious tradition includes longstanding suspicions about the Catholic Church. Criticizing the Pope also gave Trump yet another turn in the media spotlight, which is a place he finds quite comfortable.
Besides, who else was the fighter going to tangle with?
His Republican opponents seem incapable of giving Trump a real contest, and nobody in the news media was causing him to sweat. Trump was probably getting bored. Thanks to Francis, he's not bored now.
Though as different from Trump as love is from anger, Francis is similar to him in one way: He says what he thinks. Early in his papacy, he shocked fellow Catholics when reporters asked him about homosexuality -- a subject long anathema to the Vatican -- and he answered, "Who am I to judge?"
When told of Trump's criticisms as he flew home from Mexico on Thursday, the Pope said, "Thank God he said I am a political man. Because Aristotle defines a human being as a political animal: At least I am a human being. Am I a pawn? Well maybe. I will leave that up to your judgment. And a person who only thinks about making wall, wherever it may be, and not building bridges, is not a Christian."
Like Trump, the Pope does not speak without purpose.
He has doubtlessly followed the American presidential campaign more closely that Trump has followed the news from the Vatican. And just as Trump fights to win whatever prize he has in mind, the Pope has fought doggedly on behalf of the poor.
He has criticized world leaders for failing to lift-up humanity, and he has chastised leaders of his own Church for living lavishly while members of their flocks suffer. His Christianity is defined by the Jesus who threw the money changers out of the temple.
In his own effort to be Christian, he aligns himself with refugees and victims of drug trafficking and has expressed that he would err on the side of open arms and open borders. This has been his response to the refugee crisis in Europe. Is it any wonder he would criticize Trump's plan mass deportations and massive wall?
In this latest controversy, Trump, has followed his usual strategy of keeping up the fight, no matter what.
He answered the Pope by saying: "He doesn't see how Mexican leadership is outsmarting President Obama and our leadership in every aspect of negotiation" and complaining that "for a religious leader to question a person's faith is disgraceful. ... No leader, especially a religious leader, should have the right to question another man's religion or faith. They are using the Pope as a pawn, and they should be ashamed of themselves for doing so, especially when so many lives are involved and when illegal immigration is so rampant."
Of course, Francis considers Christianity his area of expertise in the same way that Trump imagines that money and power are his. And he is less inclined than Trump to be shy about stating his beliefs. When he celebrated Christmas, the birth of Jesus, last December, he offered a very un-Trumpian homily that included this:
"In a society so often intoxicated by consumerism and hedonism, wealth and extravagance, appearances and narcissism, this Child calls us to act soberly, in other words, in a way that is simple, balanced, consistent, capable of seeing and doing what is essential. ... Amid a culture of indifference which not infrequently turns ruthless, our style of life should instead be devout, filled with empathy, compassion and mercy, drawn daily from the wellspring of prayer."
Maybe Trump heard the Christmas homily and took it personally. Maybe he understood that the Pontiff -- Latin for bridge-builder -- would join the battle of ideas.
Certainly Francis is not likely to back down. He is as transformational for the church as Trump is in politics. Humble and empathetic, he might apologize for hurting Trump's feelings. But he won't abandon his position. He will always prefer bridges to walls.
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