Save up to 90% on a Hartford Courant subscription. Click here to sign up now!

National Security

Texas incident fuels concern about lone-wolf terror attacks

The attempted attack on a provocative cartoon contest in Texas appears to reflect a scenario that has long troubled national security officials: a do-it-yourself terror plot, inspired by the Islamic State extremist group and facilitated through the ease of social media.

Trying to gauge which individuals in the United States pose such threats — and how vigorously they should be monitored — is a daunting challenge for counterterrorism agencies. Some experts caution that a limited number of small-scale attacks are likely to continue.

Michael McCaul, chairman of the House Homeland Security Committee, said federal authorities are aware of "thousands" of...