Nothing wrong about "Guilt by Association" if the association is voluntary and the folks associated with were notorius before the association took place. Both conditions are satisfied in the case of Cindy S. and Code Pink, Veterans for Peace, Military Families Speak Out, etc..
That's dead on! The left vehemently denies the insidious role played by their "fellow traveller" strategy in undermining our way of life. The volume of their disingenous denials says it all!