Take backs are Trump's signature move

Journalists traveling on Air Force One to Singapore with Trump had been told that the US had decided to be part of the G7 joint communique, which represented a minimal show of unity amid deep disagreements between Trump and the other six leaders over trade. The reporters only discovered when the plane landed on the Greek island of Crete to refuel that the president had changed his mind.

  The Guardian

And why did he change his mind? Because Justin Trudeau said something he didn't like: "US Tariffs were kind of insulting" and he "will not be pushed around" according to Trump's tweet.

Even for a presidency as capricious as Trump’s, his action marked a new blurring of lines between his personal feelings towards other leaders, and US government policy.

It's not new. He's only always been acting and reacting on his personal feelings.

A few minutes before Trump sent out his inflammatory tweets, his hawkish national security security adviser, John Bolton, appeared to anticipate them by sending a tweet of his own, deriding the G7 summit he had just attended.

“Just another G7 where other countries expect America will always be their bank. The President made it clear today. No more,” Bolton said.

The two of them were probably licking each others wounded egos and pumping each other up to post indignant and retaliatory tweets.

The tweets also represent a blow to the French president Emmanuel Macron and the German chancellor Angela Merkel, who believed they had brokered a deal to smooth over tensions on US-European trade.

They still don't know Trump.

The communique said the leaders of the United States, Canada, Britain, France, Italy, Germany and Japan agreed on the need for “free, fair, and mutually beneficial trade” and the importance of fighting protectionism.

“We strive to reduce tariff barriers, non-tariff barriers and subsidies,” the statement said.

And Trump told his people not to sign it.