Anything may be possible in America, but a Palin presidency is virtually implausible.

It's an appeal as old as America and its presidency: This is an extraordinary country populated by hard-working, big-dreaming, freedom-loving people graced by God when they're not pulling themselves up by the bootstraps.

'Argo,' 'Lincoln,' and 'Zero Dark Thirty,' three films honored with Best Picture Oscar nominations, lionize their Washington-anchored protagonists as crafty, competent, and virtually incorruptible.

Once a popular Alaska governor with a modest record of accomplishment, Palin could conceivably revive her reputation in this era of short memories. But it's hard to imagine her name atop the GOP ballot in 2016, when a cast of heavyweights who sat out 2012 will be vying for the nomination.

Andrew Jackson was the first president to claim that the desires of the public overrode Congress's constitutional prerogatives. Virtually every president since Jackson has claimed the mantle, even while lacking two ingredients of an electoral mandate: a landslide victory and a specific agenda.

Say what you want to say about the rest of his presidency, including his tone-deaf response to Katrina and a war waged in Iraq on false pretenses, Bush connected with Americans in the aftermath of 9/11 because he looked as frail and unforgiving as we felt.