Sarah Palin will swoop into Iowa and New Hampshire to speak at tea party rallies this Labor Day weekend, whipping up talk she will announce her candidacy for president. After all, this coming Saturday will mark the third anniversary of her acceptance speech for vice president at the Republican National Convention – a speech which established her as both a conservative icon and a magnet for criticism. Her supporters are certainly encouraging talk she will be a 2012 candidate. Peter Singleton, her Iowa political organizer, told National Review’s Robert Costa last month: “I believe she will run. Labor Day will...