SAM DONALDSON, ABC NEWS - Last month, President Clinton called for cooperation among nations in the fight against drugs. But what if the people who are supposed to be keeping drugs out of the United States instead are putting the government smack in the middle of dealing drugs? Tonight, a six-month PrimeTime investigation reveals how agents of the US Customs Service turned a pot smuggler into a big-time cocaine kingpin and then turned a blind eye while he poured billions of dollars of cocaine on to the streets of America. Tonight, Forrest Sawyer talks to Rodney Matthews, a smuggler turned top informant who became one of the biggest embarrassment s in US Customs history. [continues 4222 words]