I think they have now changed the number from 21 to something else maybe 31 is what I have heardSo I finished reading Agenda 21. My take is that The Overton Window is about what is happening in the here and now and Agenda 21 is about what will happen in the there and then if something isn't done about what is happening in the here and now.
But it's Glenn Beck. Sometimes I think he is right on the money and other times I think he is drinking again. Agenda 21 has several pages in the back of the book about the research that was done in writing it.