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Vice President Joe Biden says he's torn when it comes to the presidential election — he still questions his decision not to run and regrets not going with a different message while campaigning for Hillary Clinton.

In a series of interviews with Jonathan Alter, published in The New York Times Magazine on Tuesday, Biden said he wished "to hell" he'd kept repeating the positive messages from his Democratic National Convention speech in July and said more about Clinton's plan for the middle class, as opposed to focusing so much on Donald Trump's lack of qualifications for office. He's also still coming to grips with not running for president himself — before his son, Beau Biden, died of brain cancer in 2015, he encouraged his father to run, but the vice president was told by several friends, including President Obama, that he wasn't ready emotionally. Biden concedes that he was "more broken" over his son's death than he thought he was at the time. "I don't know what I'd do if I was in a debate and someone said, 'You're doing this because of your son,'" he said. "I might have walked over and kicked his ass."

On Trump, Biden says the president-elect reminds him of the bullies from his childhood who mocked him for having a stutter, and wherever he goes, he's asked if "American leadership" is "going to continue." Biden admitted he's worried about what might happen should Trump be all bluster and no action when it comes to matters of global importance — if Trump "just stays behind the lines — hands off — it could be very ugly. Very, very ugly," he said, adding: "It's like a Rubik's Cube trying to figure this guy out. We have no freakin' idea what he's gonna do." Read more about Biden's thoughts on Trump, how he became close friends with Obama, and the advice he received as a freshman senator that helps him while working with Republicans, at The New York Times Magazine.