Joe Biden debuts his first nickname for Donald Trump

Former Vice President Joe Biden is trying to play Donald Trump's nickname game, but his first try – "President Tweety" – is a far cry from the sinister and suggestive "Lyin' Ted" or "Crooked Hillary" monikers.

The president has used nicknames for his political foes since he first was a presidential candidate back in 2015. He used monikers like those to raise questions among GOP voters about the truth-telling of 2016 primary foe Ted Cruz of Texas then among swing voters about the ethics of former Secretary of State Hillary Clinton.

Mr Trump helped deliver a knockout punch on his final 2016 GOP primary opponents, Florida Senator Marco Rubio, by calling him "Lil Marco." It was a suggestion that Mr Rubio lacked the might and fortitude to be the president of the United States.

He boasted last August that he was responsible for Massachusetts Senator Elizabeth Warren's early struggles as a presidential candidate.

"Like, Elizabeth Warren – I did the 'Pocahontas' thing," Trump told a chuckling-in-unison crowd of supporters in Manchester, New Hampshire, on 15 August. "I hit her really hard and it looked like she was down and out." That nickname is based on Ms Warren's own admitted false statements about having Native American ancestry.

Fast forward nearly a year, and Mr Biden has all but captured the Democratic nomination. He has endorsements from both Ms Clinton and Ms Warren.

But, after once challenging the president to a fist fight, Mr Biden has resisted matching Mr Trump in the incumbent's unique game of bare-knuckle politics.

That changed on Monday.

"Trump is out there tweeting again this morning. I call him 'President Tweety!'" Mr Biden said in a video message posted online on Monday.

The moniker, at first glance, seems more cute than biting – see: "Pocahontas" and "Crooked Hillary." After all, his rally crowds still chant "Lock her up!" about Ms Clinton.

Mr Biden's wading into the Trump nickname pool amounts to a reversal. Just last week, he told Vanity Fair he was holding back on playing the president's name game.

"Trump is a master at laying nicknames on people. I can hardly wait to get onto the stage with Donald Trump,' he said. 'I'm really resisting giving a nickname to' the president.'

Experts and political operatives call Mr Trump's tactics effective, noting the cumulative effect of the monikers help him with the broader slash-and-burn approach he takes to politics and the presidency.

"Whose burn was sickest? Who cares? Regrettably, none of this is a laughing matter," journalist Jon Allsop, who has studied the impact of Trump's rhetoric and nicknames, wrote in the Columbia Journalism Review.

"Trump's nicknames ... recall the age-old storytelling techniques found in myths and fairy tales," he wrote. "Consciously or not, Trump uses epithets and nicknames to set the narrative around his political opponents, boxing them in with unflattering stereotypes that can be hard to escape.