ANALYSIS — One of the world’s most unlikely world leader bromances appears to be over.

President Donald Trump and French President Emmanuel Macron clashed Tuesday in a remarkable question-and-answer session with reporters that was broadcast around the globe. From U.S.-French trade to Turkey’s invasion of northern Syria and the Islamic State’s posture there to a clear disagreement about the role of NATO, the two leaders who once wooed one another jousted and interrupted one another for nearly 45 minutes during an alliance meeting in London.

Macron is a 41-year-old French liberal. Trump is a 73-year-old American conservative. Yet, the French leader was eager to curry favor with the then-new American commander in chief — he made Trump the guest of honor at his country’s 2017 Bastille Day celebration. Trump was quick to reciprocate, hosting his French counterpart a year later during a chummy visit that included a tree-planting on the White House’s South Lawn and his first state dinner.

Since, the duo has drifted.

[Trump relishes in casting France’s Macron as new bad boy of NATO]

Trump kicked off the two-day alliance leaders’ meeting in the British capital by bashing Macron for saying NATO is suffering from a “brain drain.” Trump lashed out during a separate, and somehow longer, question-and-answer session with reporters. He called the remark “dangerous” and “insulting” to the alliance’s other members. The two countries also exchanged trade threats, and the U.S. president delivered it personally while sitting just feet from Macron.

The list of issues on which they disagreed during their remarkable public meeting is long, but here are three takeaways:

Strained alliance

Trump, especially as a presidential candidate in 2016, was perhaps the world’s top NATO critic. Macron was known as a believer in such international institutions. Times have changed.

“NATO has come a long way in three years. It’s something we’re very proud of,” Trump said, a striking statement from a president who has sharply criticized his alliance counterparts for more than three years. “It serves a great function.”

Then the shot-taking began.

“I don’t believe the president is very involved,” he said of Macron, who tilted his head and squinted, “and likes the idea of NATO.”

The American president said the alliance’s primary functions and missions are shifting, still retaining a fundamental objective of countering Russia while focusing more on violent Islamic extremist groups and China’s rise. Macron just isn’t there yet.

“I do stand by them,” the youthful French leader said, calling for a debate and assessment of “what NATO is and should be.”

[Impeachment cloud to follow Trump across pond for ‘celebratory’ NATO meeting]

Trump clearly suggested France should devote more of hits national budget to its defense — and, by extension, the mutual defense of all alliance members. Macron pushed back, sometimes extending his left arm to interrupt or signal the older American leader it was his turn to speak — and, often, offer a different view.

“It’s not just about money,” he said. “I do believe we do pay what we have to pay.”

“We have to be clear on the fundamentals of what NATO should be,” Macron said, suggesting the alliance should retain its initial goal: Maintaining “peace in Europe.”

The session’s most awkward moment came when Trump publicly asked the French president if he would take in ISIS detainees from his country who now are in U.S. custody. Macron responded with lengthy remarks about fighting the group and the situation in Syria.

“That’s why he’s a great politician,” Trump said mockingly. “That was one of the great non-answers I’ve ever heard.” It was time for Macron’s arm again, as he interrupted the American to say his country “actually has taken back some fighters.”

Turkey leftovers

Democratic lawmakers back home — joined by many Republicans — have criticized Trump for being too soft on Turkish President Recep Tayyip Erdogan, saying the U.S. president essentially approved the Turkish leader’s military operation against Kurds, a longtime U.S. ally, in northern Syria. Add Macron to that list, as he let his frustrations show in a very public setting.

[Impeachment latest: Trump calls Democrats ‘unpatriotic’ at NATO summit]

“We need clarification from the Turkish side,” he said, on how it can be a member of an alliance established to guard against Russian aggression while buying a Russian-made air defense system. He also wants more clarity from Turkey on its objectives in northern Syria and in its conflict with the Kurds.

Trump, however, is just fine with Erdogan’s actions.

“We have a very good relationship with President Erdogan,” he said, adding he told the sometimes-hardline Turkish leader, “‘You can control your own border now, I don’t care who you do it with.’ … I can’t speak for the president of France.”

No need. Macron was doing just fine on his own.

After Trump blamed Turkey’s purchase of the Russian defense system on the Obama administration’s yearslong blocking of Ankara’s proposed purchase of the U.S.-made Patriot air defense platform, an animated Macron rejected his counterpart’s claims, saying there also was a “European option.”

“They decided not to be compliant with NATO,” he said of Turkish officials, gesturing wildly as he spoke.

Wine war

The duo met one day after a report surfaced that Trump is considering slapping 100 percent tariffs on some French imports like wine, cheese and handbags in retaliation to what his administration says is unfair treatment of U.S. technology firms from Paris.

During his first appearance before reporters, Trump appeared to confirm the report. But later, he left himself some wiggle room.

[Road ahead: impeachment progress, judicial nominations and a Christmas tree]

“We have a minor dispute,” he said alongside Macron. “I think we will probably be able to work it out.”

But minutes later, Trump again issued a threat: “We’ll work out some mutually beneficial tax. … I don’t know if it’ll come to that, but it might.”

The U.S. president sent stock markets sliding with an earlier assessment that a “phase one” trade deal with China he announced in October might not be finalized before the end of the year after all.