Outside the Middle East, in the five years since 9/11, there have been terrorist attacks carried out in Bali, Mumbai, Casablanca, Madrid, and London. As evidenced by the June 2006 arrests in Toronto and the August 2006 arrests in London, the formal links with Al Qaeda have become increasingly tenuous, yet the pool of radical jihadists is growing. We will be attacked again, despite our overseas exertions. It is as inevitable as a hurricane, earthquake, or major flood. And as with those recognized disasters, there are things we can be doing right now to reduce our exposure to the catastrophes.

So where do we go from here? Americans need to make building resiliency from within as important a national enterprise as confronting dangers from without. When it comes to terrorism, it’s important to remember that terrorists are interested in carrying out attacks where they have near-certain odds of generating the maximum consequences. We are not talking about an unbounded problem. There are a finite number of meaningful targets worth attacking. Chemical and energy facilities near urban population centers have the potential to inflict the greatest casualties; attacks on the electric grid, oil and gas facilities, major ports, and the food-supply system have the potential to create the greatest cascading economic effects, at a price tag that would be in the billions. Defending the targets that would be most appealing to terrorists and investing adequate resources in safeguarding them are worth doing. Unbelievably, the Department of Homeland Security did not even have a good working list of the nation’s most critical structures until late 2006 — and most of the items on that list are a long way from being protected.

The expense involved in making our catastrophic terrorism targets less attractive is far from overwhelming, especially when measured against the $250 million the US has been spending every day since the spring of 2003 on the war in Iraq. The LNG facility outside Boston would be considerably safer in a remote location near the harbor’s entrance or farther offshore, which would mean tankers wouldn’t need to transit so close to a densely populated area. If attacked, the fire would be spectacular, but the consequences would not. The Coast Guard should also do more to reach out to the people who live, work, and play on Boston’s waterfront to educate the very people who might witness a dry run or actual event. Our most important and largely untapped national assets are everyday citizens, who too often are kept in the dark about the details of potential terrorist attacks. We would do well to heed Thomas Jefferson’s famous admonition, “A nation’s best defense is an educated citizenry.”

Stephen Flynn, a former US Coast Guard commander, is the Jeane J. Kirkpatrick senior fellow for national-security studies at the Council of Foreign Relations.

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