In private, Mark Cuban has started discussing his role in national politics with his family.

He told Business Insider, for instance, that he spoke with loved ones about his decision to campaign on the trail for Democratic presidential candidate Hillary Clinton.

"We discussed how much of a threat I believe Trump to be," Cuban said in an email. "We discussed why it was important to me to get involved — that if I could have an impact and didn't try, it would have left me guessing forever."

And, as Cuban said, his family feels "like we started on the right path" to "have a platform and voice for the future."

Cuban, 58, is a self-made billionaire businessman and the owner of the Dallas Mavericks. And he seems more serious than ever about running for president.

Cuban refrained from engaging much in politics before the 2016 campaign cycle. But in the past two years he has openly flirted with a White House bid, teasing journalists with tantalizing words about his aspirations.

It wasn't long ago that Cuban was shutting down questions about whether he'd seek the presidency one day, flatly rejecting the notion, as he did at the September presidential debate.

But something changed. It was, as Cuban put it, "obvious": the election — unpredictability — of Trump.

"What I do depends on how things play out for the country," Cuban said referring to a 2020 attempt at unseating Trump.