• When President Trump refused to sign off on the final communiqué of a G-7 meeting in Canada, there were warning signs that he might do the same at the NATO summit meeting last month.

He didn’t — and now we may know why.

Senior U.S. officials pushed to finalize a NATO deal before the meeting even began, in an effort to ensure that Mr. Trump did not reject it. The rushed machinations were another sign of the lengths to which the president’s top advisers will go to protect the alliance from Mr. Trump’s antipathy.