World leaders are learning to play President Trump using his own set of predictable negotiating tricks. The most vivid example of this: French President Emmanuel Macron bragging to Trump that he was jamming him by stealing "The Art of the Deal" techniques, Axios has learned.

The scene: Perched on white leather armchairs in their bilateral meeting on the sidelines of the NATO Summit in Brussels, Trump and Macron soon turned to the unavoidable subject: The expanding trade war between the United States and Europe.

Trump, after whacking the Europeans with steel and aluminum tariffs, has been frustrated by the European Union's retribution. The Europeans have designed tariffs with the goal of inflicting as much political pain as possible on Trump. They targeted Kentucky's bourbon industry, Harley Davidson motorcycles and America's iconic Levi brand jeans.

During their tête-à-tête, Trump suggested to Macron that he tell the European Union they ought to negotiate with the U.S., according to a source familiar with the conversation.

Macron replied that no, actually he was not in favor of negotiating under threat.

"I read the Art of the Deal," the French president told Trump, with a smile. "I know that we need to retaliate first so we have some leverage in the negotiation."

Why it matters: Like many foreign leaders, Macron has learned that the only language the U.S. president understands is the un-nuanced, transactional language of dealmaking and the blunt projection of strength. It's why Trump is drawn to strongmen and belittles those he considers "weak" like Canada's Trudeau (whom Trump publicly refers to as "Justin.")

What we're hearing: A senior Trump administration official told me another story that illuminates this part of Trump's mindset. As we know, Trump was glued to the television as former FBI director James Comey testified before Congress on March 20 of 2017.

Trump would never admit this publicly, but he told people afterwards that he was impressed by the performance of his Democratic nemesis Adam Schiff. Trump hates Schiff and calls him a horrible liar. But he marveled at Schiff's tough and surgical opening statement that day.

More than six months after the hearing, Trump told an aide how impressive he considered Schiff's performance to be. "This is like September or October last year," a source who discussed the matter with Trump recalled. "Trump was like, 'I watched that [Schiff's statement] and thought I had committed a crime!'"

"He has respect for the adversaries that have the balls to take it to him like he takes it to them," the source added.

The Chinese have absorbed this lesson the best. They have engaged in a trade war with no armistice in sight. Trump has threatened the Chinese with tariffs on more than $500 billion of Chinese imports; but, as we've reported, he's playing a dangerous game. China is fully prepared to retaliate and out-wait America.

The bottom line: President Xi is playing Trump's game with a much better political hand. The Chinese leader enjoys the advantages of authoritarianism — "president for life" as Trump admiringly calls him.