If America was based on religion and christianity, why have all of our values changed?

Why is everyone getting divorced, who claim to be devout Christians. Why are we so greedy and ignore the homeless on the streets when we claim to be so moralistic and altruistic. Why were so many boys molested by priests? Why are christians so scared of change and differences in people? Why when we founded America, the south had slaves? I mean would Jesus have slaves. Why do republicans only care about money and power, but then they say they are the religious right? I wonder why many educated and successful Americans turn their backs to the church, now that i see the truth about the real christianity.