We all knew it was only a matter of time before John Bolton got involved with the impeachment scandal. In fact, on the very first day that news of the whistleblower broke, we applauded the idea that Bolton could be the whistleblower behind what would ultimately launch the inquiry. He's not, but it sure seems like the former national security adviser, fired by Donald Trump last month, might be wreaking havoc.

According to Trump's former advisor on Russia, Fiona Hill -- who testified in front of the House impeachment inquiry yesterday -- Bolton pushed back against the dealings in Ukraine of Rudy Giuliani and Gordon Sondland. From the NYTimes:

Mr. Bolton told [Fiona Hill] to notify the chief lawyer for the National Security Council about a rogue effort by Mr. Sondland, Mr. Giuliani and Mick Mulvaney, the acting White House chief of staff, according to the people familiar with the testimony.

"I am not part of whatever drug deal Sondland and Mulvaney are cooking up," Mr. Bolton, a Yale-trained lawyer, told Ms. Hill to tell White House lawyers, according to two people at the deposition. (Another person in the room initially said Mr. Bolton referred to Mr. Giuliani and Mr. Mulvaney, but two others said he cited Mr. Sondland.)

It was not the first time Mr. Bolton expressed grave concerns to Ms. Hill about the campaign being run by Mr. Giuliani. "Giuliani's a hand grenade who's going to blow everybody up," Ms. Hill quoted Mr. Bolton as saying during an earlier conversation.

According to Hill, Trump also put Sondland -- the ambassador to the EU -- in charge of the relationship with Ukraine, even though it is not in the EU.

Meanwhile, The Daily Beast is reporting that Trump, himself, has long suspected Bolton of being behind many of the leaks inside the White House.

In the course of casual conversations with advisers and friends, President Trump has privately raised suspicions that a spiteful John Bolton, his notoriously hawkish former national security adviser, could be one of the sources behind the flood of leaks against him, three people familiar with the comments said. At one point, one of those sources recalled, Trump guessed that Bolton was behind one of the anonymous accounts that listed the former national security adviser as one of the top officials most disturbed by the Ukraine-related efforts of Trump and Rudy Giuliani, the president's personal attorney who remains at the center of activities that spurred the impeachment inquiry.

"[Trump] was clearly implying [it, saying] something to the effect of, 'Oh, gee, I wonder who the source on that could be,'" this source said, referring to the president's speculation. Bolton, for his part, told The Daily Beast last month that allegations that he was a leaker in Trump's midst are "flatly incorrect."

Rudy, meanwhile, is taking issue with being called a "hand grenade" by Bolton.

.@RudyGiuliani on Bolton calling him a "hand grenade." RG: "I'm very disappointed that his bitterness drives him to attack a friend falsely...It's really ironic that John Bolton is calling anyone else a hand grenade. When John is described by many as an atomic bomb . "

— Kristen Welker (@kwelkernbc) October 15, 2019

Reminder: John Bolton is a horrible human being. He is notoriously hawkish and was in fact the architect behind the Iraq War. Basically, he came into the Administration with one goal in mind: To start a war with Iran. Even Trump pushed back against Bolton's more hawkish tendencies. That said, he is a Yale-trained lawyer, and while he is a goddamn war criminal, he at least understands that it's not OK to use a foreign power to interfere in our elections.

According to The Business Insider, the FBI has also been "rattled" by Trump's "brazenness."

"You walk down the halls and there was this sense of dread, and everyone's kind of thinking, did the president really do this?" the agent said.

The agent was one of four current and former officials Insider spoke with about the matter. In addition to feeling undermined by the Justice Department's ongoing investigation into the Russia probe's origins, sources also said FBI officials were frustrated with how the Justice Department handled a criminal referral related to a whistleblower's allegations against Trump, saying it added to a sense that the bureau was being "neutered."

As Democrats continue to expand their impeachment inquiry, morale inside the White House is low, while Mick Mulvaney and the White House Counsel, Pat Cipollone -- who is developing the impeachment strategy -- are at odds. I'm sure the disaster in Syria is not helping matters.

Meanwhile, the backdrop to much of this is the bitter, divisive divorce that Rudy Giuliani is going through, if you're interested in that drama. The important takeaway, however, is that Giuliani's soon-to-be-ex-wife thinks that Rudy is hiding money from her, and while Rudy says that he's been working for Trump pro bono, he's getting paid a lot for representing the two men who were arrested last week, Lev Parnas and Igor Fruman.

If I'm following this correctly, Rudy has spent months arguing that Hunter Biden was paid an absurd amount of money based on political connections and not actual professional skill, all while being paid half a million dollars for his political connections https://t.co/uDhVRTr6AV

— Sam Stein (@samstein) October 15, 2019

And speaking of Hunter Biden, just to bring this whole mess full circle, he recently resigned from the board of that Chinese company, and he gave an interview this morning admitting that he wouldn't have gotten the gig on the gas company in Ukraine if his last name were not Biden, but saying that he didn't do anything unethical.

Hunter Biden, former Vice President Joseph R. Biden Jr.'s son, acknowledged in an interview to be broadcast on Tuesday that he probably would not have been named to the board of a foreign company if his last name weren't Biden, but he rejected suggestions by President Trump that he and his father had engaged in wrongdoing.

"Did I make a mistake? Maybe in the grand scheme of things," Mr. Biden said in an interview with ABC News, which published excerpts from it on Tuesday morning. "But did I make a mistake based on some ethical lapse? Absolutely not."

"I don't think there's a lot of things that would have happened in my life if my last name wasn't Biden," Mr. Biden told Amy Robach of ABC.

That's fair. At least he owns up to his privilege and nepotism, unlike the Trump kids. In any respect, there's another Democratic debate tonight, and I am sure that Hunter Biden's name will come up more than a few times.