Speaking of unsecured debts, what if I refuse to pay?

If I own $18,000 to credit cards issuers(Amer Express, Bank One, WomanWithin) and I stop paying any for months...what next? Especially since I think the old way of the credit rating system is obsolete or dead. Like my parents in the 1950s, I need not a credit system anymore in this life. Even moving to a 3rd world country before this year ends, permanently(railroad disability annuity)! Where all is cash and carry. They don't even know what an American Express is or a credit rating.