Trump and the former presidents, along with their spouses, all sat together in Washington National Cathedral, the site for the state funeral. George H.W. Bush, the 41st president — who called for a kinder, gentler nation — died Friday at 94.
When Trump arrived, he and the first lady shook hands with the Obamas and sat down next to them. Barack Obama, a Democrat, has been a frequent target of the Republican Trump, who has moved to undo his predecessor's policies.
There are also tensions among Trump and the Clintons. Trump repeatedly bashed Hillary Clinton, the 2016 Democratic presidential nominee, during the last election race.
The apparent harmony is a remarkable statement about our country, said Fagen, a CNBC contributor.
"To see all these presidents and world leaders come together to pay their respects for somebody who devoted their life to public service is something we can all take pride in as Americans," she said.
"[I] certainly hope that we see this pattern of civility, at least at key moments in the nation's history, survive," she added.