Can the Trump-Macron bromance last?
History is replete with ground-breaking bonds forged between world leaders. Think of Franklin Roosevelt and Winston Churchill, Richard Nixon and Mao Tze-Tung, Bill Clinton and Yasser Arafat.
But one of the most confounding alliances was unveiled this week in Washington, when French President Emanuel Macron arrived for a state visit with American President Donald J. Trump.
Mr Trump and Mr Macron's time together was punctuated by unusual affection among heads of state: intricate handshakes, kisses, holding hands, caressing each others' shoulders, and hugs.
Macron, 40, bade farewell with a smarmy email that oozed French charm, and included the flattery that Mr Trump, 71, is known to enjoy.
But Macron didn't even wait to leave Washington before he ripped into many of Mr Trump's policies and reiterated his deep concern over climate change, a polar opposite to the disdain that prompted Mr Trump to withdraw from the global Paris Climate Accords.
"We are killing our planet. Let us face it: There is no planet B," Mr Macron told a joint session of the US Congress.
As if he couldn't hold it in any longer, Mr Macron rolled out a long list of his own global priorities, beginning his preferred way to settle trade disputes (take them to the World Trade Organisation, not impose tariffs as Mr Trump is doing.
He received rousing applause when he quoted Franklin Roosevelt's famous inaugural address, in which he declared, "the only thing we have to fear is fear itself".
Mr Macron said isolation and withdrawal "can be tempting to us as a temporary remedy to our fears. But closing the door to the world will not stop the evolution of the world. It will not douse, but inflame the fears of our citizens."
The speech, and Mr Macron's earlier insistence that France would remain in a nuclear disarmament treaty with Iran, made people wonder: why stage a bromance and then counter it with criticism?
Macron walking a diplomatic tightrope
Mr Macron is walking a diplomatic tightrope. Europe needs someone who can communicate with Mr Trump, and communicate back to Europe what he is thinking and how he is likely to act.
Mr Macron, in a sense, is playing the role of the global leader who takes Mr Trump's temperature.
But he also may wind up being the subject of Mr Trump's ire if the mercurial President believes that he has been double-dealt by the crafty French politician. In fact, Mr Macron said Wednesday that he believed Mr Trump would pull out of the Iran deal for domestic policy reasons.
The relationship is hardly one cemented in a shared outlook. After all, Mr Macron patterned his election campaign on that of Mr Trump's predecessor, Barack Obama, even securing Obama's endorsement in a video that aired during the campaign.
That alone might cause Mr Trump to question his motives. But Mr Trump also needs Mr Macron to make him look legitimate to the rest of the world. If Mr Macron and his wife can come to D.C. and cordially consort with the Trumps, then perhaps other leaders can follow suit.
Champagne toasts and manly kisses not new
For history buffs, the Trump-Macron relationship brings to mind another unlikely global friendship a generation ago.
In 1972, then president Richard Nixon and Soviet Communist Party leader Leonid Brezhnev met in Moscow to sign a series of treaties.
The summit followed Nixon's historic visit to China a few months earlier, and at first, it almost seemed like Brezhnev was acting cool to the American leader.
He did not greet him at the airport, and the welcome was decided low-key compared with the May Day shows of military might that the Soviets liked to put on for the world.
But then came an unexpected 105-minute meeting at the Kremlin, and the emergence of a new phrase: "detente."
In the months that followed, the pair began displaying their own friendliness, with cordial handshakes, bear hugs, laughter, champagne toasts and manly kisses.
It's too soon to tell whether the Trump-Macron relationship will yield the same kind of results as the American-Soviet one.
However, it has already had one payoff, in the US participation in a coalition with France and Britain that has conducted air strikes in Syria.
Macron's warmth contrasts Melania's cool
For Mr Trump, however, the affection from Mr Macron makes up for the coolness he sometimes encounters from his wife, Melania.
As the two couples stood at attention during a ceremony this week, she appeared to swat his fingers away before allowing him to hold her hand.
External Link: Trump tweet: Our two great republics are linked together by the timeless bonds of history, culture, and destiny. We are people who cherish our values, protect our civilization, and recognize the image of God in every human soul.
There was no such hesitation on Macron's part, who gave Trump a multi-part handshake that verged on the theatrical, as did his description of "dear Donald".
And Trump, at least, seems to get what Macron is about.
"Both President Macron and I understand our responsibility to prioritize the interests of our countries and, at the same time, to be respectful of the world in which we live," Mr Trump said, in a White House statement.
"The friendship between our two nations — and ourselves, I might add — is unbreakable."
At least, until he decides otherwise.
Micheline Maynard is an author and journalist who tweets @mickimaynard