Yes.
This is perhaps a corollary to the practice pointed out by Ann Coulter. The Libs choose spokes-people who cannot be challenged because of their special status.
Sheehan is a bereaved mother of an Iraq casualty.
Brady is the near-widow of the injured Jim Brady.
Jackson is the "colored" reverend who sacrificed for civil rights in the not-quite-forgotten past.
Only a heartless Republican would challenge any of these people's right to pronounce what the government should do to improve the nation.
You're right,it does seem to be a corollary. Not to go off on a tangent,but I believe that this is what the American version of feminism has done to this country. The politics of "feelings,nothing more than feelings",and victimisation. The facts don't matter,only someone's unassailable position as a "victim". That word has become meaningless.