They have not spoken over the phone, at least to the knowledge of their aides. Neither has made any real attempt to reconcile after Trump accused Obama of ordering wiretaps at his skyscraper in New York.

Perhaps it’s a predictable outcome for two men with a long and bitter history; to be sure, the ice-out is the product of deep-rooted enmity that extends well beyond differences in policy or style.

But in the scope of recent history, it’s unprecedented for a sitting president and his predecessor to eschew even the faintest of ties.

“I don’t think they have a relationship,” said David Axelrod, who served as Obama’s senior adviser during his first years in office. “President Obama did what he could to help during the transition but, obviously, there have been intervening events.