BREAKING: The president has concluded his DVR'd edition of Fox & Friends and has started up his DVR'd edition of America's Newsroom.

50 more minutes till his first scheduled meeting of the day.

Left, Fox, 9:07 am
Right, Trump, 10:08 am pic.twitter.com/xZrsHQ3WAB

— Matthew Gertz (@MattGertz) May 7, 2018

During that segment, Fox correspondent Griff Jenkins discussed a Boston Globe report from a few days earlier about Kerry’s behind-the-scenes effort to salvage the Iran deal. Kerry “has been engaging in what some are calling shadow diplomacy,” Jenkins reported, using the same term Trump would in his subsequent tweet.

Immediately after Jenkins’ report, anchor Bill Hemmer turned to contributor Byron York, who said that Kerry’s actions were “a big deal” because Kerry was “meeting with foreign governments in an attempt to undermine the current U.S. administration.” York added that while “you will hear” that Kerry may have violated the Logan Act, “it likely does not apply here.”

Indeed, conservatives were raising the prospect that Kerry had violated the Logan Act – including Fox & Friends host Steve Doocy earlier that morning, in a segment the then-president likely watched. But as University of Texas School of Law professor Stephen Vladeck explained in the Globe report, that statute would not apply in this case, since Kerry was acting to maintain what was (at the time) current U.S. policy.

Trump’s tweet set off his supporters at the network, particularly Sean Hannity, who maintained dual roles as a close Trump adviser and primetime host. On his show that night, Hannity suggested that Kerry was “violating the law, the Logan Act,” and asked, “Where are the agents in the FBI and the DOJ breaking down John Kerry's door? Another blatant example of a two-tier justice system sadly in this country today.”

Later in the program, Hannity polled members of his panel as to whether Kerry had violated the Logan Act. After they all agreed that he had, Hannity said, “Let's see when that investigation begins.”

Fox’s criticism of Kerry continued into the next day on Fox & Friends, including a segment in which co-host Brian Kilmeade claimed his action “seems to be a violation of the Logan Act,” while his guest compared the former secretary of state to the Taliban. Roughly an hour after that, Trump tweeted, “John Kerry can’t get over the fact that he had his chance and blew it! Stay away from negotiations John, you are hurting your country!”

Later that day, Trump announced that the U.S. would withdraw from the Iran deal.

Trump’s tweets had a major and immediate impact, Berman explained in his book. The Times reported:

On May 9, Mr. Berman writes, Justice Department officials told his office that it would be responsible for an investigation into Mr. Kerry’s Iran-related conduct. The F.B.I. would join the inquiry.

The focus was on the Logan Act, a rarely invoked 1799 statute barring private citizens from unauthorized negotiations with foreign governments, which has been criticized as unconstitutionally vague. Mr. Berman notes that no one has ever been successfully prosecuted under the law.

But, as he puts it, “The conduct that had annoyed the president was now a priority of the Department of Justice.”

Although Mr. Berman says he does not know what prompted the Justice Department to seek a Kerry investigation, “No one needed to talk with Trump to know what he wanted. You could read his tweets.”