COVE POINT, Md. – Michael Bradshaw cut short the small talk and let his twin 225 horsepower Honda outboards roar. A pleasure boat was nearing the Coast Guard-enforced protection zone as the Tanaga Empat, a massive double-hulled tanker carrying volatile liquefied natural gas from Trinidad, steamed up the Chesapeake Bay.

Bradshaw and his two crewmen treat any approaching boat as if Osama bin Laden himself were speeding toward them. There’s good reason for that: Al-Qaida’s deputy leader, Ayman al Zawahri, recently called for attacks on oil infrastructure, and liquefied natural gas is a tempting target.

The Coast Guard gunboat screamed across the water until it reached the vessel, the Mary Katherine. Polite but stern, a crewman warned a surprised elderly couple to keep 500 yards away from the tanker.

“A lot of people outside, who don’t do this job, sometimes ask me what’s really going to happen on the Chesapeake Bay? Take 9-11, for instance; who thought that was ever going to happen? It could be the same thing with this,” said Bradshaw, 24, a no-nonsense bosun’s mate second class.

Two Coast Guard gunboats escorted the Tanaga Empat to the offshore loading pipeline operated by Dominion Resources. An attack at this bayside site might seem unlikely, since the Cove Point terminal isn’t near a population center, but it’s only a stone’s throw from the Calvert Cliffs nuclear power plant, which enhances its target value.

In addition, liquefied natural gas terminals in Pennsylvania and Massachusetts are near population centers, and as such imports grow, so does the threat of terrorism.

Natural gas imports are expected to double by 2023, and liquefied natural gas terminal expansion, construction or study is going on in at least 40 places along all three U.S. coastlines.

That makes the Coast Guard think.

“We’re re-evaluating our security posture with LNG tanker arrivals, and looking at what risk mitigation strategies are most appropriate,” said Cmdr. John Cushing, the chief of the Coast Guard’s vessel and facilities operating standards division in Washington. “How many boats do we need to escort these vessels into port? … There is certainly a work load associated with the number of escorts that we’d need to do.”

A Department of Energy report in December 2004 concluded that transporting liquefied natural gas has terrorism risks, ranging from deadly fireballs to vapor clouds that could burn back to the source from as far away as a mile.

The study suggested that a pleasure boat loaded with explosives, such as the one that damaged the destroyer USS Cole in Yemen in 2000, might not penetrate the double hull of a liquefied natural gas tanker. Researchers saw bigger threats from hijackers, who could crash a tanker to release a vapor cloud.