To a degree it goes without saying. But it's worth reviewing just how deeply preposterous Palin's argument yesterday really was when she claimed that she refused to exploit the people of Alaska by serving out her full term.
When you run for governor, as for president, you run for a four year term. You commit, at least implicitly, to serving four years, though many people end up not doing that for various reasons. There's nothing in the implied contract about running for reelection. Indeed it's arguable that the public would be better served by a governor focusing for four years on running the state rather than laying the groundwork for their reelection.
In any case, Gov. Palin, who's served only a little more than half her first term (remember, she was elected in 2006), announces she won't run for reelection. And having decided that she won't run for a second term, she concludes that it would be exploiting the people of Alaska to agree to serve out the remainder of the term they elected her to serve back in 2006. This is apparently because she'll be a lame duck. And, she claims, lame ducks never get anything done and just spend a lot of money going on taxpayer funded junkets. So better to walk away from her job and pass it off to the Lt. Governor who no one hired to do the job at all.
You could keep plumbing the depths of this ridiculousness for some time. But as MC rightly notes it's simply poisonous, toxic, fatal for anyone running for president. Setting side political and policy stances, the one thing really key about a president is that they be steady under pressure, not rash, and not prone to spur of the moment freak outs where they just walk away from the job to go to Disneyland. A lot of nonsense gets knocked around about 'character' in presidential elections. But this is the foundational question of character that really is critical. Assuming this isn't about some soon-to-pop scandal and it's really that Palin just decided on a moment's notice (look at how much preparation went into the press conference to know how long this was in the works) to up and walk away from her responsibilities, that's simply fatal for anyone's presidential chances.
She may resurface as a latter-day Hannity or she may found some Palin-specific Anti-Defamation League dedicated to calling out obscure bloggers who've written mean things about her. But what very little shot she had as a future presidential candidate (and it was a much longer shot than I think many realized) is over. She's done. She's back to what she was -- a small person looking for someone to be angry at.