Perhaps the best predictive tool at the disposal of policymakers is a rational understanding of both the capabilities of terror organizations and our own vulnerabilities. The bloodthirstiness of an organization like ISIS ought to be a given, considering the very nature of terrorism. But while ritual beheading, rape, slavery, torture and indiscriminate murder are shocking, they hold little predictive value. What counts is whether a terror group has the capacity to strike, and how that capacity matches up with our own weaknesses. A threat to destroy a US Navy carrier battle group, for instance, probably isn’t credible. But a threat to infiltrate hundreds of battle-hardened jihadists back into their Western home countries in order to conduct “lone wolf” attacks might be.
In many ways, the astonishing success of ISIS on the ground has sent policymakers and experts back to the drawing board. In a press conference this week, Secretary of Defense Chuck Hagel called ISIS an “imminent threat” to American interests and warned that it "poses a threat greater than 9/11. ISIL is as sophisticated and well funded as any group we have seen. They’re beyond just a terrorist group. They marry ideology with a sophisticated strategic and tactical military prowess and they’re tremendously well funded. This is way beyond anything we have seen. We must prepare for everything. Get ready.”
Similarly, America’s top-ranked military officer says the surging Islamic State group has an "apocalyptic, end-of-days strategic vision" in the Middle East and cannot be defeated unless the United States and a coalition of partners confront it head-on in Syria.
"They can be contained, not in perpetuity," Army Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told a news conference.
On the other hand, Norman McCulloch, Jr., former US Ambassador-at-Large and Coordinator for Counterterrorism at the US State Department, says claims that ISIS is a direct threat to the United States are unproven. “It’s a long-term concern,” said McCulloch, “but at the moment, there is no proven record of out-of-area activities, no demonstrated ability to carry out attacks. And if I had to say who the next attack was going to be carried out by, it wouldn’t be ISIS.”
So, what Western vulnerabilities are terrorists likely to exploit in the future? Public infrastructure remains a major concern, especially the American electrical grid and particularly nuclear power plants like the Pacific Gas & Electric facility in San Jose, CA, that came under attack by snipers last year. According to Stephen Flynn of the Center for International Security and Cooperation, ports remain a major concern. “Despite the efforts that have been put in place with regards to containerized cargo,” says Flynn “you name the contraband and it’s still flowing through this system, whether it’s knock-off products on the low end; to movements of large sums of cash; to narcotics still; to every form of weapon short of nuclear weapons.”
Cyber terrorism also looms large, particularly as it relates to aviation, banking, energy, government, and other critical sectors. To date, attacks have been directed at the West by state or state-sponsored groups, notably the Chinese and Russians, but Islamist recruitment in Western nations could eventually yield jihadists with the skills to move groups like ISIS into cyber terrorism in a major way.
Water systems, which are widely distributed and rarely hardened, are especially vulnerable to terrorist attacks using chemical or biological weapons. But even simply incapacitating water distribution in cities like Los Angeles, Phoenix or Las Vegas would have devastating effects on the national economy and could directly threaten thousands of lives.