Only a baseline allegiance to the Democratic Party -- only a deep-rooted leftist partisanship -- can explain such behavior. Any rational group, seeking to draw attention to the Iranian situation, would leap at the opportunity to host Palin, who routinely draws tens of thousands of fans.
More than that, any rational group would recognize that if high-ranking Democrats withdraw from anti-Iran rallies simply to avoid being seen in public with high-ranking Republicans, then perhaps Democrats aren't the friends of Israel they purport to be. Any rational group would be suspicious that Hillary Clinton is more concerned with Sarah Palin than Mahmoud Ahmadinejad. Any rational group would use their anti-Iran rally as a forum for candidates, allowing those with the most pro-Israel message to capitalize politically.
Instead, the organizers disinvited Palin. In doing so, they demonstrated a political bias unworthy of a pro-Israel organization. More than that: In rejecting Palin, they demonstrated loyalty to Democrats over loyalty to Jewish causes. That became especially clear when the text of Palin's un-given speech was released. "We gather here today to highlight the Iranian dictator's intentions and to call for action to thwart him," the speech reads. "He must be stopped. The world must awake to the threat this man poses to all of us. Ahmadinejad denies that the Holocaust ever took place. He dreams of being an agent in a 'Final Solution' -- the elimination of the Jewish people. He has called Israel a 'stinking corpse' that is 'on its way to annihilation.' … Iran should not be allowed to acquire nuclear weapons. Period. And in a single voice, we must be loud enough for the whole world to hear: Stop Iran!"
This is strong stuff. And it is stuff that the rally organizers abandoned when they kowtowed to Democrats rather than recognizing that support for Israel must be a non-partisan issue. It was foolish. It was dangerous. And most of all, it was dishonorable.