I knew, if we waited long enough, we’d see Sarah Palin make a sensible decision.

Sarah Palin is not running for president.

Ms. Palin, the former governor of Alaska, ended her inscrutable cat-and-mouse game with the political establishment on Wednesday afternoon by saying that she would not join the field of Republican candidates seeking her party’s nomination, but would still work to oust President Obama.

Palin announced her decision first on a right-wing radio show, explaining that she wanted to remain “unshackled,” and the presidency would apparently cramp her style. Soon after, Palin issued a statement to supporters saying that she decided not to run because her “family comes first.”

The list of possible Republicans presidential candidates who were considered contenders, but who ended up ruling out campaigns, is apparently complete and quite long: Daniels, Huckabee, Barbour, Thune, Trump, Pence, Jindal, Corker, Jeb Bush, Christie and now the infamous former half-term governor of Alaska.*

The announcement also suggests the 2012 Republican presidential field is now complete. I suppose one could make the case that Giuliani is still mulling his options, and there were some silly rumors yesterday about Eric Cantor, but given the calendar and the filing deadlines, GOP voters will have to choose among the already-announced candidates. This realization will likely push some major donors and establishment insiders to get off the fence and start picking sides.

As for Palin, whose endorsement will probably be sought aggressively by the Republican field, the announcement hardly seems to matter. Her national ambitions have been laughable for quite some time, and had she run, Palin had no credible chance of winning the nomination — even GOP voters had no respect for her — or coming close to winning the presidency.

Is the decision a surprise? Given that Palin never walked away from her Fox News contract, no, but she certainly gave mixed signals about her intentions since walking away from her elected job, half-way through her only term.

Jon Stewart joked just a week ago, “So, here’s the thing. You can have a colorful bus and drive to early primary states or you can go around telling people what you would do if you were president. But when you put those two together, there’s really only two possibilities: you are either running for the president of the United States, or you are a crazy person.”

It would appear we now know which of these two possibilities is correct.

* fixed

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.