WASHINGTON--In the short time since the advent of the social Web, the Internet has evolved into a platform for innumerable virtual communities of every stripe to gather and collaborate, so it is hardly surprising that along with sites for DIY hobbyists and recipe swaps, a growing number of online forums have emerged that give voice to radicals and extremists, in some cases serving as recruiting tools for terrorist groups.

On Tuesday, the Bipartisan Policy Center (BPC), a Washington think tank, released a report on the mounting dangers of online radicalization, urging the government to formalize a strategy for countering the threat, while at the same time steering clear of any policies that would amount to censorship or the stifling of expression on the Web.

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The report is the latest installment from the BPC's Homeland Security Project, co-chaired by former New Jersey Gov. Thomas Kean and Lee Hamilton, a former representative from Indiana. Kean and Hamilton served as the chairman and vice chairman, respectively, of the commission convened to examine the terrorist attacks of Sept. 11, 2001.

Internet Most Dangerous Innovation for Terrorists

"In its 2004 report, our 9-11 Commission showed the terrorists who attacked us on Sept. 11, 2001, even they used the Internet for searches, to buy tickets and to book hotels. Yet not a single one of them was radicalized online," Kean said at an event marking the release of the new report. "More than 10 years since [the] Sept. 11 attack, the use of the Internet to radicalize and recruit home-grown terrorists is the single most important and dangerous terrorist innovation."

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The report evaluates the challenge of curbing online radicalization from the perspective of supply and demand. It concludes that efforts to shut down websites that could serve as incubators for would-be terrorists--going after the supply--will ultimately be self-defeating, and that "filtering of Internet content is impractical in a free and open society."

"Approaches aimed at restricting freedom of speech and removing content from the Internet are not only the least desirable strategies, they are also the least effective," writes Peter Neumann, founding director of the International Centre for the Study of Radicalisation at King's College London and the author of the report.

Instead, policymakers should focus their attention on the demand side of the radicalization issue, Neumann argues, with the government spearheading outreach initiatives that would bring together schools, community groups and businesses to advance awareness and media literacy and offer a competing narrative to that presented by sites that traffic in radical propaganda.

"If there are bad ideas out there, there should be more good ideas to counter them," Neumann said on Tuesday.

Last year, the White House issued a counter-radicalization strategy and an associated implementation plan, acknowledging the key role the Internet has come to play in galvanizing violent extremists and promising to deliver a separate and detailed plan for specifically addressing the online threat. That plan has yet to appear, and in the short term, the BPC's report's "first and most important recommendation is for the White House to complete its work on the strategy, make it public, and begin its implementation with alacrity."

A Well-Informed Public Is the Best Defense

The original White House plan carries a similar emphasis on communities to the new BPC report, articulating a "significant," but limited, role for the federal government "as a facilitator, convener and source of information."

"The best defenses against violent extremist ideologies are well-informed and equipped families, local communities and local institutions," the White House plan reads.

[Related: Cybersecurity Stalls in Senate, Obama Could Issue Executive Order]

The BPC report underscores the wide ideological spectrum of radical communities that can be found online, running the gamut from supporters of al Qaeda to white supremacists and neo-Nazis, environmental extremists and animal liberationists, among many others.

With its emphasis on defusing the impact of radicalizing sites through countering messages, such as frank accounts of civilian deaths from terrorist attacks or testimonials from reformed extremists, the BPC report articulates a faith in the power of the "marketplace of ideas, in which truth prevails as long as good and bad ideas are allowed to compete."

At the same time, Neumann acknowledges the limitations of such an approach, or "market failures" in the online world, where "the cranks, extremists and conspiracy theorists now seem to be everywhere," and many people have crowded into "ever-smaller ghettos for ideas and discourses, which, in turn, have reduced the number of spaces in which extremist and/or controversial ideas are openly contested."

The report calls attention to a number of ways the government can involve itself, such as the series of online safety workshops the U.S. National Counterterrorism Center has developed in concert with Muslim community groups and other government agencies to incorporate sessions geared for parents about online radicalization along with issues like protecting kids from child predators and pornography.

Other efforts have seen the State Department develop programs overseas to organize moderate groups and amplify their voices online, as well counter-messaging initiatives that take specific aim at extremist sites through targeted blogs, Facebook groups, tweets or other platforms.

Neumann allows that these demand-side programs take time and that, even if they were deemed a categorical success, online radicalization would persist. What's more, he points out that the information that extremists post about their activities and organizations online has proven extremely useful to law enforcement officials seeking to disrupt attacks.

But those efforts are impeded by an ambiguous and outdated set of laws and policies governing how domestic agencies can monitor and analyze online communications, a problem made all the more acute by the cross-border issues inherent with the Internet, Neumann says, arguing that an effective anti-radicalization strategy must include an overhaul of the legal framework for the Internet age.

"All the existing rules for counter-terrorism, counter-radicalization distinguish between domestic and foreign," he says. "There are things you can do abroad that you cannot do at home. But the Internet, of course, does not respect that distinction. The Internet is genuinely transnational. So a website may be registered in one country, the content may be hosted in a second country, the producer of the website may be based in a third, and the user and consumer may be based in a fourth country. What are the rules that should apply--domestic or foreign? It's not always clear."

Kenneth Corbin is a Washington, D.C.-based writer who covers government and regulatory issues for CIO.com.

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