(CNN) On Monday afternoon at 4 p.m., Michael Flynn Jr. tweeted this : "You're all going down. You know who you are. Mark my word...."

Which is, um, intriguing?

Flynn is the son of Michael Flynn, President Donald Trump's former national security adviser and now a cooperating witness in special counsel Robert Mueller's probe into Russian meddling in the 2016 election and possible collusion between Russia and the Trump campaign.

You'll remember that Flynn pleaded guilty to lying to Mueller in December, and in announcing his decision, made clear that "my guilty plea and agreement to cooperate with the Special Counsel's Office reflect a decision I made in the best interests of my family and of our country."

That guilty plea came just a month after CNN reported that Flynn was growing increasingly concerned about the legal exposure of his son , who served as his de facto aide-de-camp during the campaign and for a portion of the presidential transition.

Even as his father has disappeared from public view since last December's guilty plea, Michael Flynn Jr. has continued to tweet up a storm. And at times, he has seemed to inadvertently(?), contradict the White House's official line on the Russia investigation.

Take this tweet from last month:

"American Patriot @GenFlynn did not lie to Pence (or anyone else in the admin) about his perfectly legal and appropriate conversations w Russian AMB Kislyak in Dec 2016. Why would a highly decorated military intel officer lie about something legal? Been a MSM lie from day 1."

That contention runs directly against the President's stated reason for firing Flynn : Because Flynn lied to Vice President Mike Pence about the nature and number of his contacts with Russian officials.

Flynn Jr. provided no context or follow up as to what evidence (if any) he had to back up his claim that Trump's reasoning for firing his father was false.

That's sort of the way things go for Flynn Jr.'s Twitter feed. There's a lot of boasting and braggadocio and very little in the way of provable facts. Flynn Jr. has touted the belated "#impeachObama" movement, attacked Starbucks and offered this vague warning about Google -- "Google is becoming a dangerous platform.....tread wisely..." -- all in the last 24 hours or so.

It's also worth noting that Flynn Jr. often traffics in debunked conspiracy theories -- including "Pizzagate," the idea that a pizza restaurant in Washington was running a secret pedophile ring that Hillary Clinton was somehow involved in. ( Flynn Jr. left the transition team after raising questions about "Pizzagate."

Which brings me back to Flynn Jr.'s "You're all going down" tweet.

The wording creates lots and lots of questions.

The biggest one is who is the "you" Flynn Jr. is referring to? Is it people within the Trump administration who he thinks have sold his dad out? Is it the alleged "deep state" actors like former FBI Director James Comey, former deputy FBI director Andrew McCabe and special counsel Mueller? Someone else?

A quick reading of Flynn Jr.'s other tweets sent around the same time -- and there are lots -- suggests he might be talking about the "deep state" idea. Why? Because, hours later, Flynn Jr. retweeted Sharyl Attkisson's story detailing something called a "sensitive matter team" within the FBI that, according to Attkisson, was tasked with dealing with the Russia investigation.

Which is, I mean ... who knows?

Look. It's easy to dismiss Flynn Jr. as a son looking out for his dad and/or someone prone to see conspiracy everywhere he looks. Maybe that's all this "you're all going down" tweet is -- just another empty boast.

But it's also worth remembering that Flynn Jr. was his father's closest aide. He was, therefore, intimately involved in the Trump campaign and, for a time, the Trump transition. Which mean he knows things. Which makes totally laughing off his latest warning a mistake.