President Donald Trump describes his summer break from Washington as a working vacation, and he’s definitely not giving his Twitter fingers a holiday.

The president unleashed a string of tweets Monday accusing CNN, all three broadcast networks and the New York Times and Washington Post of non-stop “fake news,” blasting a Democratic critic as “a phony Vietnam con artist” and insisting that his political base is growing stronger, contrary to public opinion polls that show his job approval rating at a historic low.

“The Trump base is far bigger & stronger than ever before (despite some phony Fake News polling). Look at rallies in Penn, Iowa, Ohio … and West Virginia,” the president tweeted Monday morning.

“The fact is the Fake News Russian collusion story, record Stock Market, border security, military strength, jobs … Supreme Court pick, economic enthusiasm, deregulation & so much more have driven the Trump base even closer together. Will never change!

“Hard to believe that with 24/7 #Fake News on CNN, ABC, NBC, CBS, NYTIMES & WAPO, the Trump base is getting stronger!”

Trump began a 17-day vacation on Friday, but his administration has portrayed it as a mandated absence so workers can replace the White House West Wing’s heating and cooling systems. They say Trump’s time at his private golf club in New Jersey will be a working vacation.

And the president made that pitch himself Monday in between Twitter targets.

“Working hard from New Jersey while White House goes through long planned renovation,” Trump tweeted. “Going to New York next week for more meetings.”

Minutes later he was back on the attack, denouncing frequent Trump target Democratic Sen. Richard Blumenthal.

“Interesting to watch Senator Richard Blumenthal of Connecticut talking about hoax Russian collusion when he was a phony Vietnam con artist!” Trump tweeted.

“Never in U.S. history has anyone lied or defrauded voters like Senator Richard Blumenthal. He told stories about his Vietnam battles and … conquests, how brave he was, and it was all a lie. He cried like a baby and begged for forgiveness like a child. Now he judges collusion?”

And apparently, the Connecticut Democrat continued to annoy the president throughout the day.

Nearly nine hours after his initial morning fusillade, president lobbed another Twitter grenade at Blumenthal.

“I think Senator Blumenthal should take a nice long vacation in Vietnam, where he lied about his service, so he can at least say he was there,” Trump tweeted.

Both Blumenthal and Trump received five military deferments during Vietnam, the New York Times reports. Blumenthal did eventually serve in Marine Reserve unit in Washington, D.C., but later said he falsely said he “served in Vietnam.” Blumental’s false statements were exposed in 2010, but there was no evidence he spoke of specific battles or conquests, the newspaper reported.

The Connecticut senator responded to Trump on Twitter Monday.

“Mr. President: Your bullying hasn’t worked before and it won’t work now. No one is above the law,” Blumenthal tweeted. . This issue isn’t about me – it’s about the Special Counsel’s independence and integrity.”

As for Trump’s base, the Gallup Organization has reported that Trump has a historic low for newly elected presidents in their first summer on the job.  Gallup reported Monday that 37 percent of Americans approved of the job Trump was doing, and 56 percent disapproved.

Those are almost an exact reversal of Barack Obama’s numbers at a comparable point in the Democrat’s presidency. In August 2009, 56 percent of voters gave Obama a favorable job approval rating, and 37 percent disapproved.