A federal judge has dismissed a $475 million defamation lawsuit that former President Donald J. Trump filed against CNN, ruling that all of the CNN statements that Mr. Trump cited were opinion and, therefore, Mr. Trump could not sue for defamation. The suit, which the former president filed in October in U.S. District Court in Fort Lauderdale, Fla., alleged a “campaign of dissuasion in the form of libel and slander” that, Mr. Trump asserted, had escalated “as CNN fears the plaintiff will run for president in 2024.” The lawsuit said that the network’s use of the phrase “the big lie”...