Ryan Greer for New America: One overarching challenge to improving counterterrorism tactics is that much of the policy revolution in the last few years has been a revolution in speech or in structure, but only rarely in funding or action, let alone in evaluation to assess what even works.

For example, consider the challenge of sharing information on foreign fighters. Providing this information to Interpol may involve reducing sensitive data (e.g., intelligence derived from a war zone) to only what is appropriate for law enforcement and also may reasonably be assumed to fall into the hands of any Interpol member, including Russia, who could misuse information provided by the U.S. or other sources. … These challenges highlight that encouraging trust among global partners is paramount, that bilateral exchanges of information are still critical for sensitive issues, and that both civil liberties and intelligence concerns must be represented throughout the policy process.