religion will be the hardest for many to swallow because most people are tainted by the confusion that the major religions cause in hiding the truth from people. Even that truth may not be the truth but religious people will get violent and that includes christians who just happen to be some of the most hypocritical monsters there are.
which might be a good thing or it might be what people try to use as justification for creating a world religion such as the noahide. just depends on how bad it becomes.