Barack Obama: “Today we are reminded that, as a nation, there's nothing we can't do when we put our shoulders to the wheel.”

They're meant to remind us of who we can be, to remind us of what's possible, so we can forge ahead.

Of course, we did not accomplish everything we set out to do. No administration does. Some of the exhibits reflect unfinished business, in some cases, my own shortcomings and mistakes, in some cases because - as a sign I kept on the…

She knew she was going to mess me up, and she did it anyway.

That was fantastic. I was a little tall for it.