Nation's Challenge: Terrorist Next Door

As I write this, helicopters circle overhead, monitoring the ongoing hunt for the alleged Boston Marathon bomber. Dzhokhar Tsarnaev, a 19-year-old Cambridge resident said to be the second attacker, grew up a few blocks away and went to high school down the street. He is, literally, the kid next door.

Most Americans think that the battlefield for terrorism is overseas. I, too, have spent the last few years studying terrorist groups abroad, interviewing violent extremists in Afghanistan, Yemen, and beyond, and evaluating the effectiveness of U.S. counterterrorism efforts internationally.

But events over the last week — simultaneous blasts at the Boston Marathon finish line that killed three and injured more than 170, the tense law enforcement investigation that followed, and the manhunt that continues at this moment — are a haunting reminder that the terrorist threat is alive and well in America. That we are not immune.

Over the last few years, U.S. officials have become increasingly concerned with the potential growth of homegrown terrorism. There have been dozens of attempted domestic terror attacks thwarted by law enforcement and a concerning trend in terrorism worldwide — the ever more decentralized nature of al-Qaeda and al-Qaeda affiliates, and increasing numbers of self-radicalized, violent jihadists who target their home countries.

After incidents like the 2009 Fort Hood massacre and the 2010 attempted car bombing in Times Square, it was natural to wonder whether Americans or U.S. residents were being radicalized, how serious a threat they posed, and, of course, what to do about it.

Unfortunately, answers to these questions prove as frustrating as the problem itself. Most domestic terrorists are American citizens, but they represent a variety of races, ethnicities, and nationalities — including Caucasians, African Americans, and Hispanics, Arabs and non-Arabs, Pakistanis, Somalis, and, yes, even Chechens.

Nearly all domestically radicalized terrorists have been Muslims, though widespread mistrust of Islam would be misplaced; more than three million Muslims live in the United States, and only a select few have turned to jihad. Some have been high school dropouts, but many have had university-level schooling or graduate degrees.

In many cases, the Internet and social-media networks were sources of radicalization. In some instances, the Internet also provided direction for how to carry out attacks, including via an al-Qaeda in the Arabian Peninsula online magazine that described how to "build a bomb in the kitchen of your mom." But other domestic terrorists were radicalized through personal contacts and received instruction at overseas terrorist training camps.

Despite this confused picture of homegrown terrorism, a few next steps are clear.

First, U.S. officials must continue developing adaptable strategies specifically geared to this evolving domestic threat. Intelligence collection has been critical thus far, helping successfully defuse many attempted attacks in the early stages, including the 2007 planned attack on Fort Dix, N.J., by six radical Islamists.

Cooperation among federal, state, and local law enforcement agencies has also been beneficial since 9/11, particularly in the area of information-sharing. This must continue. But, moving forward, there needs to be improved efforts to link law enforcement investigations with broader intelligence-collection efforts, to better understand the process of radicalization and jihadist recruitment in the United States, and to improve community-based warning systems.

This also means that, in the weeks ahead, it is critical to avoid a public backlash against the American Muslim community.

Muslims are often the primary targets for jihadist recruiting. But alienating this group will only make it harder to address the threat, hampering intelligence collection and undermining community-based counter-radicalization efforts.

Active support from and cooperation with American Muslims will be one of the most effective ways to thwart future terrorist attacks. As Saudi counterterrorism officials continually remind me, the friends and family of potential jihadists are the best form of defense against radicalization. This approach works in America, too.

But the most critical element of America's response to the evolving terror threat is to strengthen our resilience to attacks of this nature. In part, this means ongoing efforts to boost emergency response training and preparation. Here in Boston, well-trained, well-prepared first responders saved lives and minimized the wider impact of Monday's attack. That will always be essential.

After the dust settles in Boston, it will also be vital for U.S. officials to put recent events into a broader national security context, while reminding the American public that no effort to combat the terrorist threat will be foolproof. Terrorism is an unfortunate reality, even in America.

I learned early Friday that one of my neighbors is a terrorist. But I still believe that the willingness of Americans to welcome foreigners, embrace other religions and cultures, and remain resilient in the face of this domestic terror threat is the most effective counterterrorism tool we have.