At last weekend's meeting of the G-7 group of industrialized nations in France, President Donald Trump performed like a bull who carries his own china shop with him.

Indeed, the G-7 has morphed into the G-6-plus-one, with the six working hard to circumscribe damage done by America's leader.

In his chosen role as global disrupter-in-chief, Trump sent markets plunging and rising with daily shifts in position on China tariffs, defended Vladimir Putin's invasion of Crimea, and boycotted a session on global warming. He showed no interest in joining with fellow democratic leaders to tackle huge global problems.

The message from Biarritz was clear: Trump has abdicated the postwar role of U.S. president as leader of the free world.

Make no mistake, White House efforts to paint this G-7 as a picture of allied unity are wholly belied by Trump's actions. True, President Emmanuel Macron, the skillful French host, managed to preclude any Trump eruption into open hostility toward fellow leaders, as happened at last year's G-7 in Canada. No doubt the U.S. president was mindful that jittery markets would react badly to any public tantrums.

Yet a look at the president's performance on five points makes clear just how much pottery was still smashed.

• Trade dispute with China

The best way to corral Beijing into changing its mercantilist policies would be for Trump to coordinate with America's European and Asian allies, who have similar complaints. Instead, Trump pursued his unilateral trade war with Beijing over the weekend with stunning incoherence, publicly shifting position on whether to raise tariffs each day.

When a journalist asked whether it was a good strategy "to call President Xi Jinping an enemy one day and then say relations are great the next day," Trump replied, "It's the way I negotiate. It's done very well for me over the years."

On Friday, Trump "ordered" American companies to leave China — an illegal command worthy of a Chinese autocrat. At Biarritz, he repeated false claims that China had paid $100 billion in tariffs to the U.S. Treasury. (U.S. importers pay the levies and pass the charges on to U.S. consumers.)

Rather than displaying a united front towards China, Trump is determined to go solo, threatening the U.S. economy and the world's.

• Putin's annexation of Crimea

At the G-7, Trump insisted Russia be invited to rejoin the former G-8, after being kicked out in 2014 for annexing Crimea. Bizarrely, Trump claimed Putin's ouster was President Barack Obama's fault. In other words, Putin's breaking of a clear post-World War II taboo — invading a neighbor — was immaterial.

Trump even tried to justify the Kremlin's seizure of Crimea by implying Russia needed the territory to base submarines. He indicated he would invite Putin to the G-7 when the United States hosts the meeting next year. Nothing could illustrate more clearly Trump's indifference to democratic values — and to allying with those who share those values, like the G-6.

• Iranian President Hassan Rohani

The G-6 opposed Trump's decision to pull out of the nuclear pact with Tehran, and would like to facilitate a return of Washington and Tehran to the bargaining table. So Macron cleverly invited Iranian Foreign Minister Javad Zarif to Biarritz in hope of promoting talks between Trump and Rouhani. But Trump's lack of a coherent Iran strategy makes such a meeting doubtful (both sides have already set daunting preconditions). Without strong U.S. leadership, Macron and the Europeans can't do diplomacy alone.

• Global warming

The presence of an empty chair at the G-7 session on global warming made clear Trump's unwillingness to confront one of the world's foremost threats. More grotesque, Trump openly lied about his absence, claiming he had conflicting meetings scheduled with Chancellor Angela Merkel and Indian President Narendra Modi. Refuting that claim, photographs showed Merkel and Modi at the global warming session.

• The next G-7 at Trump's Doral resort in Miami

The president's fervent and lengthy promotion pitch for a troubled property reveals once again that he can't distinguish his office from heading his real estate business. His effort to use the White house to enrich his own brand would not only violate the Constitution but puts his presidency on a par with corrupt third world leaders'.

Trudy Rubin is a columnist and editorial-board member for the Philadelphia Inquirer. Email her at trubin@phillynews.com.

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