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Good morning.

Here’s what you need to know:

• President Trump in Warsaw.

The American leader, visiting Poland before heading to a Group of 20 summit meeting in Germany, cast the West’s battle against “radical Islamic terrorism” as a way to protect “our civilization and our way of life.”

Mr. Trump also signaled a tougher line against Russia, a day before a sit-down with President Vladimir Putin, but he still refused to concede that Moscow was solely responsible for meddling in the 2016 U.S. election. The meeting with Mr. Putin will be watched closely — not least by Mr. Trump’s aides, who don’t know what the American president plans to say.

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