STEVE INSKEEP, HOST:
The president's appearance at that memorial service came on the same day he joined with all his living predecessors. He met with Jimmy Carter, Bill Clinton, George H.W. Bush and George W. Bush, whose presidential library was dedicated in Texas.
A photograph, sent out on Twitter incidentally, by former President Clinton, shows the five men in a circle, chatting. Three Democrats joined two Republicans on a day when political differences were overlooked.
Here's NPR national political correspondent Don Gonyea.