The day opened at 5 a.m. with Sarah Palin, whose seven-and-a-half minute video statement captured with precision the bubbling anger and resentment that is an undercurrent of the national conversation about our public discourse.

It ended with President Obama, whose plea for civility, love and compassion — for us to all be not just better citizens but better people — exposed for the first time the emotions of a leader who has spent two years staying cool and controlled for a nation beset by difficult times.

The tone of the two speeches could not have been more different. The venues were a world apart — the smallness of a rectangular video on a computer screen and the vastness of an echo-filled basketball arena…

Unless — or until — Ms. Palin runs for president and wins the Republican nomination, there are not likely to be many single days in which the two very different politicians are on display in such dramatic ways.