"Desperate and defensive, Trump sends one crazed tweet after another — insinuating that the whistleblower should be executed, threatening to prosecute the chairman of the House Intelligence Committee, warning direly of civil war,” Biden said.

Biden also called Trump a “bully” and praises the “courageous” whistleblower who first brought the matter to light but whose identity, for now, remains unknown.

The vociferousness of Biden’s pushback against Trump also speaks to concerns by Democrats that the president’s attacks could have an effect on his candidacy.

The president and the Republican National Committee last week announced a $10 million ad buy, some of which will underwrite attack ads that advance an dubious claim that Biden, as vice president, pressured a prosecutor in Ukraine to drop an investigation into a natural gas company because it hired his son, Hunter Biden, in 2015 for consulting work.

Numerous Ukrainian officials and independent media reports have found no reliable evidence for Trump’s accusation that the investigation was ongoing at the time the prosecutor, Viktor Shokin, was pressured to quit or that Biden used improper pressure on behalf of his son. At that time, a coalition of Ukrainian and international groups was pushing for Shokin to be removed for corruption.

"He is repeatedly smearing me and my family. His party fans out to carry the smear. Millions of dollars in dishonest attack ads are blanketing the airwaves — paid for by the special interests so well served by his presidency,” Biden said in his remarks.

Shokin has claimed in an affidavit that he was fired because of Biden and his son, which Trump’s legal team recently mentioned without disclosing the ties it has to Shokin in a case involving a one-time business partner of Trump’s former campaign manager, who’s now in prison for financial fraud.

“We weren’t pressing Ukraine to get rid of a tough prosecutor. We’re pursuing Ukraine to replace a weak prosecutor who wouldn’t do his job,” Biden said. “Trump on the other hand was secretly putting at risk our national security by pursuing a personal political vendetta against me because I don’t think he wants to run against me.”

Biden amplified that theme later in his speech.

“He imagines that this tactic will allow him to pick his opponent and face only the candidates he thinks he can beat,” Biden said. “Well, we’re not going to let Donald Trump choose the Democratic candidate.”

Trump has accused Biden of lying about his son's business dealings. The former vice president last month said he had “never spoken to my son” about his work overseas, but Hunter Biden had told the New Yorker that he at one point had mentioned his Ukrainian consulting work to his father.

On Wednesday, the president tweeted a video clip of Biden making the denial before transitioning to a picture of the Bidens playing golf along with another man identified as a “Ukrainian gas exec.” The tweet also includes a snippet of the 2005 video “Photograph” by the rock group Nickelback.

To Biden, Trump’s “antics” are a distraction.

"It’s important to step back from the heated 24-hour news cycle and focus carefully on the larger story. It’s not about Donald Trump’s antics. It’s about what has brought Donald Trump, and the nation, to this sobering moment in our history — and to the choice facing us in 2020,” Biden said.

"What has brought us here is simply this: The abuse of power.”

Biden made clear the election and his candidacy was about one thing: defeating Trump.

“A lot of my opponents say we have to do more than just beat Donald Trump. I agree,” Biden said. "We have to do more than beat Donald Trump. We have to beat him like a drum."