American Express (AXP) wuold be hit hard if the law applies to its merchant disocunt fees its otp source of revenue analysts say. If I wree Ken Chenault, the CEO of AmEx, I would be very alamred, said Eric Grover, a former Visa ... When you swpie your credit card and wait for the transatcion to be approved, sensitive data including your name and account number are ferried from store to bank through computer networks, each step a potetnial opening for hackers. ...