Bharara is a classic federal prosecutor in the Southern District of New York, always looking to make headlines as much as meaningful collars. He earned the enmity of Reason readers in 2015 when his office subpoenaed information about

the records of six people who left hyperbolic comments at the website about the federal judge who oversaw the controversial conviction of Silk Road founder Ross Ulbricht. Shortly after the        subpoena was issued, the government issued a gag order prohibiting Reason not only from discussing the matter but even acknowledging the existence of the subpoena or the gag order          itself. As a wide variety of media outlets have noted, such actions on the part of the government are not only fundamentally misguided and misdirected, they have a tangible chilling effect on      free expression by commenters and publications alike....

   The subpoena also covered...harmless comments as: "I hope there is a special place in hell reserved for that horrible woman," and "I'd prefer a hellish place on Earth be reserved for her as       well.

I don't know if an investigation into Website commenters falls within the cautionary notion of a "chilling effect on the press" but it's pretty damned close. That phrase normally is invoked to protect the press's confidential relationship with sources against investigations by law enforcement, but it might be extended to try to protect the identities of people responding to news article. If a news organization has to give up the identity of its readers/commenters, it's a slippery slope to having give up your sources. 

The gag order about the subpoena and the gag order itself is incredibly obnoxious and oppressive. So sorry, but an investigation into the identity of Web commenters is newsworthy and should be reported by Reason. What did Bharara hope to gain by this silencing order? And the last sentence if accurate, shows the overreach of the subpoena and points up Lazy8's notion of credible threat. 
FWIW:

https://www.nytimes.com/aponline/2017/03/12/us/ap-us-federal-prosecutors-resignations.html

The request for resignations from the 46 prosecutors who were holdovers from the Obama administration wasn't shocking. It's fairly customary for the 93 U.S. attorneys to leave their posts once a new president is in office, and many had already left or were making plans for their departures. 

But the abrupt nature of the dismissals — done with little explanation and not always with the customary thanks for years of service — stunned and angered some of those left behind in offices around the country.

One NYT article I recently read noted that Bill Clinton dismissed all 93 US attorneys when he took office in January 1993.