WaPo's Eugene Robinson puts it well.
Activists for Latino and immigrant rights — and supporters of sane governance — held weekend rallies denouncing the new law and vowing to do everything they can to overturn it. But where was the Tea Party crowd? Isn’t the whole premise of the Tea Party movement that overreaching government poses a grave threat to individual freedom? It seems to me that a law allowing individuals to be detained and interrogated on a whim — and requiring legal residents to carry identification documents, as in a police state — would send the Tea Partyers into apoplexy. Or is there some kind of exception if the people whose freedoms are being taken away happen to have brown skin and might speak Spanish?