What did Donald Trump do today?

He tried to halt publication of a book that paints him in an unflattering light.

Today, Trump's lawyers sent an 11-page cease and desist letter to Henry Holt & Company, the publisher's of Michael Wolff’s forthcoming book, Fire and Fury. The book paints a picture of a mentally failing Trump surrounded by staff who never expected him to win, and who are horrified by how unfit he is for the job. "My indelible impression," Wolff wrote in one excerpt, "of talking to [Trump's staff] and observing them through much of the first year of his presidency, is that they all — 100 percent — came to believe he was incapable of functioning in his job."

Trump's threat of a lawsuit is completely empty. For one thing, the standard for prevailing in a libel suit is much higher for public figures like elected officials, because of the protections the First Amendment offers to Americans who criticize their government. Even worse for Trump, as he learned when he sued author Tim O'Brien over a different book, the people sued are entitled to a defense, and that defense often turns up or publicizes far more damaging information.

Trump has threatened — but failed — to sue for defamation at least 40 times. In five suits that were actually filed, Trump lost or withdrew from four of them, and the fifth was a small part of a much larger and unrelated lawsuit against the broadcaster Univision's decision not to air Trump's Miss America pageant. That case was settled.

In response to the threat, the publisher moved up the release date to tomorrow.

Why does this matter?

• Freedom of speech is more important than a president's feelings.

• If Trump didn't want people hearing about what Wolff was saying, it's hard to imagine a less effective strategy than this.