Complex sentence: Members of White supremacist movements often repeat the accusation of media control as part of their conspiracy theories about Jewish world domination, and they sometimes assert that Jewish control of the media is exerted to prevent the supremacists from publicizing their messages to mainstream America.
Split into simpler sentences: Members of White supremacist movements often repeat the accusation of media control as part of their conspiracy theories about Jewish world domination. They sometimes assert that Jewish control of the media is exerted to prevent the supremacists from publicizing their messages to mainstream America.