In my very sour moments (too frequent these days) I think that so much Christianity in America is infantilized adults praying to a great Santa Claus in the Sky who carries a sack of toys in one hand and a whip in the other. If we're good children and obey Daddy, then our wishes will come true. Sometimes, I think "Jesus is Lord" and "Jesus is My Personal Savior" are just different ways of saying "My Heart Belongs to Daddy."
As for Prosperity Gospel, it's a cargo cult with Christian trimmings.
How else to explain why so many Americans keep the Bible and Atlas Shrugged on the same shelf?