Seldom has Donald Trump paid a real price for ridiculing anyone he sees as a political threat, or for that matter, anyone he doesn’t particularly like. Running a long-shot campaign in 2016, Trump taunted the then–Fox News anchor Megyn Kelly (“There was blood coming out of her eyes, blood coming out of her wherever”); demeaned Khizr and Ghazala Khan, the parents of a soldier killed in Iraq; and insulted the war hero John McCain for getting shot down in Vietnam (“I like people that weren’t captured”). None of it stopped him from becoming president.

Former Vice President Joe Biden is only a few days into his 2020 presidential bid, and already Trump is road testing various lines of attack. For now, he has settled on “Sleepy Joe,” though advisers say Trump is still casting about for the artfully emasculating nickname that felled his erstwhile Republican rival Jeb Bush, he of “low energy.”

When Biden’s name would come up in White House meetings early in Trump’s term, the president “would be totally dismissive of him,” the former White House strategist and Trump campaign CEO Steve Bannon told me. “Trump will bench-press Biden on the debate stage if it ever gets to that.”

Trump may take steps to see that it doesn’t. Typically, presidents stay out of the other party’s nomination fights. Trump will find it tough to resist injecting himself into the race. But the coming Biden evisceration may prove to be more brutal than anything the president has yet unleashed. Make no mistake: Team Trump sees Biden as a genuine threat to the 45th president’s second term. The campaign’s internal polling aligns with public polls showing Biden to be Trump’s most dangerous general-election opponent, one of the president’s confidants said. The Real Clear Politics average of national polling shows Biden leading Trump by nearly 8 percentage points.