Complex sentence: The September 11 attacks also heightened the perceived threat of terrorism-related piracy, but U.S. Maritime Administration (MARAD) experts distinguish terrorism from piracy, and piracy from shore gangs who rob ships in port.
Split into simpler sentences: The September 11 attacks also heightened the perceived threat of terrorism-related piracy. However, U.S. Maritime Administration (MARAD) experts point to the need to distinguish terrorism from piracy, and piracy from shore gangs who rob ships in port.