Carnivore was used to track suspected American extremists when they traveled abroad. What type of technology was it?

Carnivore was one of the pioneering technologies employed for Internet surveillance, particularly in the context of monitoring online communications and activities. Developed by the FBI, it functioned as an email interception system that allowed the agency to filter and analyze vast amounts of digital data for potential national security threats.

This technology was significant because it represented an early attempt to adapt law enforcement capabilities to the rapidly evolving digital landscape, which posed unique challenges for monitoring and gathering intelligence on individuals' online behavior. Manifesting as a tool for tracking and gathering evidence on suspected extremists, Carnivore allowed law enforcement agencies to observe interactions that took place online, particularly as many individuals were beginning to use the internet for communication and organization.

While the other options hint at various aspects of national security and surveillance, they do not accurately capture the fundamental purpose and nature of Carnivore as a tech-centric monitoring tool designed specifically for electronic communication. This understanding underscores the broader trends of how technology has increasingly been utilized in the realm of national security and surveillance.