WASHINGTON—President Trump bucked most of his top national-security advisers by abandoning retaliatory strikes in Iran on Thursday. In private conversations Friday, Mr. Trump reveled in his judgment, certain about his decision to call off the attacks while speaking of his administration as if removed from the center of it.

“These people want to push us into a war, and it’s so disgusting,” Mr. Trump told one confidant about his own inner circle of advisers. “We don’t need any more wars.”

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