Counterterrorism should focus on cruise ships.

Maritime counterterrorism efforts are too focused on port security and cargo containers, leaving cruise ships and ferries wide open to the possibility of deadly and costly terrorist attacks, according to a book-length study of the issue by Rand Corp.

The report, Maritime and Terrorism: Risk and Liability, says cruise ships and ferry lines need more protection against terrorism attacks because they meet terrorists' prerequisites for an attack: The damage would be highly visible, would kill many people, would destroy costly property and would interrupt trade.

Currently, the United States government is focusing its maritime efforts on port security and securing cargo containers, the ships that carry them and the freight carriers that take containers in and out of ports. But focusing on cargo containers and ports without also securing cruise ships and ferries "is like bolting down the front door of a house and leaving the back door wide open," the report said.

The study also said a maritime terrorist attack will create complicated liability issues that would make it difficult to compensate victims. The United States currently has "ambiguous liability standards in the maritime terrorism context," owing to conflicts in the law.

"Civil liability standards in maritime terrorist attacks against the United States will likely draw on specialized rules in admiralty, particularly with regard to attacks on ferries and cruise ships," the report said. "Related rules include liability standards for personal injury and death, regulatory requirements pertaining to vessel security, and statutory limits on liability for vessel owners. Admiralty jurisdiction over these sorts of claims may preempt competing legal rules that would otherwise apply on land and may limit the compensation that can be sought by victims in some circumstances."

The report contained some good news, in that there is little evidence terrorists and pirate syndicates are in cahoots. Pirates, the report said, rely on maritime trade to be operating smoothly, while terrorists are motivated to disrupt it. Also, the report said, some commonly anticipated attacks probably aren't attractive for terrorist groups because they wouldn't work. Sinking a cargo ship with an improvised explosive device to block a commercial shipping route--one common scenario--would be difficult owing to modern ship design, and sunken ships even then could be cleared quickly from shipping lanes. "Maritime terrorism policy should not be motivated by these perceived threats," the report said.

The greatest risk to shipping, the report said, would be a nuclear device smuggled into the United States in a shipping container. But that, the report concluded, was far less likely than what it judged to be the greatest risk to human life: an attack on a cruise ship or ferry. Possible attacks there would be far easier to carry out, the report said, and might take the form of an onboard bomb or a biological agent tainting the food or water.

The report also made a handful of policy suggestions, including a recommendation that the U.S. government "increase attention to the control of nuclear weapons and materials" to keep a possible nuclear device from sneaking in through a cargo container. "Policies must balance the need for reducing the risk with the need to keep shipping open," the report said.