The top U.S. military officer overseeing South and Central America said Wednesday that his forces interdict only about 25 percent of all the observed illicit drug shipments transiting from his region to the United States, routes the military has reason to believe Iran might someday seek to exploit. Air Force Gen. Douglas Fraser, commander of U.S. Southern Command, told reporters that because of declining maritime resources and increases in the flow of illegal drugs, his forces are forced to simply let the remaining shipments go. Furthermore, Fraser said, there is evidence that Iran — through surrogates, namely militant groups Hamas and Hezbollah — could be looking to exploit drug routes into the United States to perhaps some day launch attacks against the U.S. mainland.