critics of the kpd accused it of having pursued a sectarian policy, e.g. the social democratic party criticized the kpd's thesis of "social fascism" (which addressed the spd as the communist's main enemy). this scuttled any possibility of a united front with the spd against the rising power of the national socialists. these allegations were repudiated by supporters of the kpd as it was said the right-wing leadership of the spd rejected the proposals of the kpd to unite for the defeat of fascism. the spd leaders were accused of having countered kpd efforts to form a united front of the working class. for instance, after franz von papen's government carried out a coup d'état in prussia the kpd called for a general strike and turned to the spd leadership for joint struggle, but the spd leaders again refused to cooperate with the kpd.