More than three years after leaving the White House, Barack Obama appears to have taken up renewed residency.
Not within its living quarters but, rather, inside President Donald Trump's head.
In a barrage remarkable even by Trump's norm-demolishing standards, the nation's 45th chief executive has spent a good deal of time lately savaging the 44th.
Suddenly, a two-way race has turned into a three-way tangle.
That may have been somewhat inevitable, seeing as how Joe Biden, the presumptive Democratic nominee, spent eight years in the White House as Obama's vice president; an attack on Obama is, by extension, a blow struck against his good friend and former workmate.
But political calculation aside, the volume of attacks from the president and the level of personal vitriol are of a wholly different order, transcending the usual partisan sniping. Among Obama's trespasses, Trump has accused him -- without substantiation or much clarity -- of committing "the biggest political crime and scandal in the history of the USA, by FAR."
Trump backers might argue that Obama started the latest round of vituperation.
In a conference call this month with alumni of his administration, the former president described Trump's handling of the COVID-19 pandemic as "an absolute chaotic disaster" and criticized the Justice Department for saying it would drop its criminal case against former national security advisor Michael Flynn.
"That's the kind of stuff where you begin to get worried that basic -- not just institutional norms -- but our basic understanding of rule of law is at risk," Obama said. With 3,000 people dialing in, he must have known his remarks were bound to leak.
Trump's eruption soon followed and his molten rage has scarcely let up. In a barrage of Tweets and television appearances, he accused Obama of abusing his office and operating the most inept and corrupt administration ever. "OBAMAGATE makes Watergate look small time!" he wrote, offering a hazy theory implicating the former president in Flynn's prosecution.