Sen. Blumenthal went on TV and suggested Don Jr. lied to Congress. Trump attacked him immediately.

Senate Judiciary Committee member Richard Blumenthal (D-CT) raised concerns about the truthfulness of Donald Trump Jr.’s congressional testimony on Rachel Maddow’s show Tuesday evening — and almost immediately provoked a vicious attack from the president as a result.

Blumenthal told Maddow he has “serious issues” concerning the “truthfulness” of the testimony Trump associates offered to his committee, and he singled out Trump Jr. in particular:

I was in the room when a great many of these witnesses appeared before the Senate Judiciary Committee behind closed doors. I think many of them should be called back to testify in public, and I hope that will true of other congressional committees as well. Because behind closed doors, there arose in my mind very clear questions — serious issues — concerning their truthfulness. And that issue pertained particularly to Donald Trump Jr. in a number of his contentions before our committee. So I think this common thread of lying to Congress and particularly to congressional committees may ensnare a number of other potential targets in the special counsel’s investigation, and become a matter of criminal action.

Blumenthal made those comments at 9:38 pm. Eight minutes later, President Trump — who also spent his morning live-tweeting cable news — laid into him on Twitter, calling him “An embarrassment to our Country!” because “he defrauded the American people about his so called War Hero status in Vietnam.”

Blumenthal’s comments come days after longtime Trump confidant Roger Stone was indicted on charges of making false statements to Congress about his contacts with WikiLeaks (among other alleged crimes), which Trump’s top intelligence officials have accused of acting as a Kremlin cutout during the 2016 election.

During his testimony to the Senate Judiciary Committee in September 2017, Donald Trump Jr. claimed he “wasn’t involved” in the Trump Organization’s efforts to build a tower in Moscow, “was not” aware that longtime Trump lawyer and fixer Michael Cohen had reached out to the Kremlin directly about it, and suggested that Cohen’s efforts to work with Russian-born developer Felix Sater on the project ended prior to 2016.

But his sworn testimony is difficult to square with details contained in November 2018 court filings pertaining to Cohen’s plea agreement, which assert that the effort to get Trump Tower Moscow off the ground continued well into 2016 and happened with the Trump family’s direct knowledge.

According to Mueller’s filing, Cohen “briefed family members of Individual 1 [Donald Trump] within the Company about the project” in Moscow:

COHEN discussed the status and progress of the Moscow Project with Individual 1 [Trump] on more than the three occasions COHEN claimed to the Committee, and he briefed family members of Individual 1 within the Company about the project.

While it’s unclear which “family members” the filings refer to, given Trump Jr.’s role as one of the top Trump Organization officials, it’s hard to imagine he wasn’t among them. Don Jr., Eric Trump, and Ivanka Trump are all family members of Trump’s who were working at the time for the Trump Organization.

In recent weeks, even President Trump’s personal lawyer, Rudy Giuliani, has indicated that Trump was directly involved in Trump Tower Moscow talks until the latter stages of the campaign — a timeline that doesn’t square with Trump Jr.’s testimony.

Stone’s indictment indicates Trump Jr. may yet face consequences for his dubious congressional testimony. And his dad didn’t seem happy about Blumenthal pointing it out.

Monday evening was far from the first time that Trump has attacked Blumenthal for his Vietnam-era military service.

It is true that Blumenthal misrepresented his military record on more than one occasion. Although the senator said things like “we have learned something important since the days that I served in Vietnam” during public remarks, he was never actually deployed in Vietnam when he was in the Marine Corps between 1970 and 1976. In other instances, however, Blumenthal correctly described his record.

When the New York Times broke news about the discrepancy between Blumenthal’s words and his actual military record in 2010, he apologized, saying in a statement, “At times when I have sought to honor veterans, I have not been as clear or precise as I should have been about my service in the Marine Corps Reserves. ... I have firmly and clearly expressed regret and taken responsibility for my words. I have made mistakes and I am sorry. I truly regret offending anyone. I will always champion the cause of Connecticut’s and our nation’s veterans.”

There is also an element of hypocrisy in Trump’s attacks on Blumenthal over his military record, seeing as how Trump received five draft deferments — one due to bone spurs in his foot — and never served in the military at all.

Trump, of course, didn’t lash out at Blumenthal on Monday evening because of newfound concerns over his comments about his military service — he lashed out because of his comments on Maddow.

Trump’s tweet attacking Blumenthal wasn’t the only indication on Monday that he’s uneasy about where the multiple ongoing investigations into his campaign are headed. During an awkward exchange with a reporter earlier in the day, Matthew Whitaker, a Trump loyalist who’s serving as acting attorney general, unsteadily revealed that the Mueller investigation is “close to being completed.”

The timing of Whitaker’s announcement is notable, given that it came on the first business day following Stone’s arrest.

Also notable is Whitaker’s revelation that he’s now been “fully briefed” on the Mueller investigation. Despite the fact that he originally came to Trump’s attention because of his cable news appearances where he would attack the Mueller investigation, Whitaker has refused to follow the guidance of Justice Department ethics officials and recuse himself from overseeing the Mueller probe — meaning he’s now in position to fire Mueller if that’s what Trump wants him to do.

Follow Aaron Rupar on Twitter. Read more of Vox’s policy and politics coverage each day at Vox.com/policy-and-politics.