Nearly two years ago, as Jeffrey Sallet prepared to take over as the leader of the FBI’s Chicago field office in 2017, he said the city’s struggle with gun violence already kept him up at night.

Now, on his way out, Sallet said he still loses sleep about violent crime and other mass acts of violence. What doesn’t keep him up at night, he said, is another topic that has roared back into the headlines during his tenure — public corruption.

“I don’t lose sleep about the corruption,” Sallet said in an exit interview with the Chicago Sun-Times. “The people that are corrupt public officials, I assure you, are losing sleep about us. And I think that’s more evident now.”

Sallet, 48, is set to leave Chicago later this month for a new job in Washington, D.C., where he said he will essentially serve as chief financial officer and chief property officer for the FBI. Though he’s leaving town, he said he has fallen in love with Chicago and hopes to return when his career at the agency is done.

His successor has yet to be announced.

When Sallet arrived, Chicago’s headlines revolved around gun violence, mass shootings and police reform. Then, the FBI in November raided the City Hall office of Ald. Edward M. Burke (14th). It turned out to be a thunderclap that not only upended the mayor’s race, but refocused attention on public corruption.

Since then, Burke has been hit with a 59-page racketeering indictment. Former Ald. Danny Solis (25th) has been outed as a cooperator who recorded Burke. Ald. Carrie Austin (34th) has landed in the crosshairs of a federal grand jury. State Sen. Thomas Cullerton also found himself under indictment. And associates of Illinois House Speaker Mike Madigan have been circled by the feds.

Sallet declined to answer questions about specific investigations when he met with the Sun-Times last week. And records show much of the groundwork for those cases was laid before Sallet came to town. Rather, Sallet praised the federal public corruption team in Chicago — agents and prosecutors on the ground — as “second to none.”

He also said the FBI aims to send the message that “the people of the City of Chicago should demand and expect honest government.”

“Anybody who is getting shaken down by a politician should come in and tell us because it’s unacceptable, and I promise you, we’re going to do something about it,” Sallet said.

Sallet, whose new job title in Washington will be associate executive assistant director of the Finance and Facilities Division, joined the FBI in 1997. He has served as a supervisory special agent managing La Cosa Nostra investigations and also worked in New York.

In Boston, where he served as assistant special agent in charge, he helped hunt for the Boston Marathon bombers after nearly finishing the race himself in 2013. In 2014, he became chief of the public corruption and civil rights section of the FBI’s criminal investigative division. He came to Chicago after leading the field office in New Orleans.

Sallet said he does, still, lose sleep about violence in Chicago. Murder totals in the city have dropped in the last few years, according to numbers kept by the Chicago Sun-Times, but totals in 2018 still outpaced 2014 and 2015.

To blame the city’s violence problem on the Chicago Police Department is not fair, Sallet said. He complimented CPD and insisted, “we need an all-society approach.” He encouraged people to “lead from where you stand.”

“This city is filled with great people . . . in all neighborhoods,” Sallet said. “And all those great people need to get together and try to agree on some things to get stuff done.”

It’s traumatic when young children head to school routinely hearing gunshots, Sallet said. He noted that it also causes trauma when police officers are left to work the same violent beats for years, and he pointed to a recent increase in officer suicides.

“I think people think police officers are robotic, and they’re not,” Sallet said. “They’re human beings.”

After last year’s mass shooting at a high school in Parkland, Florida, Sallet said the Chicago FBI rolled out a new squad made up of roughly 17 agencies and 34 people. He said it “addresses, on a daily basis, all the mass-acts-of-violence complaints we get in the entire Northern District of Illinois.” The executive board of the agency’s Joint Terrorism Task Force has also expanded to over 120 members.

Success stories in preventing mass violence happen every day, Sallet said. He pointed to the man, armed with an assault rifle, who last month opened fire inside and outside the Jesse Brown VA Medical Center but was arrested within 30 seconds by the hospital police. Sallet said the man also, crucially, ran out of bullets.

Bernard Harvey Jr., the alleged gunman, now faces a federal gun charge.

“I don’t think people realize how lucky we were,” Sallet said.