Oh that's easy. First, read Rammbo's comment. After that consider the possibility that Obama represents the pinnacle of America-hate. America-hating young people existed prior to Obama.
Better yet consider the blast of negative comments over Paul Ryan and compare that to what America was trying to PREVENT in the Viet-Nam war. Yet the young long-haired peace-nik hippie free-love drug induced efforts WANTED us to leave Viet-Nam so that Viet Cong could continue their human rights atrocities.