Washington: If President Donald Trump would actually sue Steve Bannon for violating a nondisclosure agreement made with his campaign, it would be great for the freedom of speech.

That may sound strange, because Trump's threatened lawsuit is precisely aimed to silence Bannon and other potential leakers who worked on the campaign. Bannon has been extensively quoted in excerpts published this week from the journalist Michael Wolff's new book, Fire and Fury: Inside the Trump White House.

But Trump's suit would almost certainly fail, and that's why it would serve free speech. Faced with an attempt to suppress speech that is so plainly of public importance and interest, a judge would have little choice but to conclude that the First Amendment disallows enforcement of an NDA made with a presidential campaign. The legal precedent created - and publicity it received - would be a blow to the bullying use of the courts to silence speech and a boon to free expression.

Start with Trump's threat. His lawyer, Charles Harder - who successfully represented Hulk Hogan in his invasion of privacy suit against the website Gawker - wrote to Bannon on Wednesday that he had breached his NDA with the Trump campaign by "communicating with author Michael Wolff about Mr. Trump, his family members, and the Company, disclosing Confidential Information to Mr Wolff, and making disparaging statements and in some cases outright defamatory statements to Mr. Wolff about Mr Trump, his family members, and the Company."