What is HSI primarily responsible for enforcing regarding arms?

The primary responsibility of HSI (Homeland Security Investigations) regarding arms relates to enforcement of regulations surrounding the export of firearms and related items. HSI plays a key role in ensuring compliance with U.S. export laws, particularly with items that could potentially be used to cause harm or that may fall under international arms control agreements. This enforcement includes investigating illegal export activities and preventing the trafficking of arms to unauthorized parties or regions.

While HSI also has a role in other areas of arms regulation, such as importation, manufacturing, and distribution, its focus on export enforcement is significant given the potential implications for national security and compliance with international treaties. The emphasis on exports aligns with the agency's mission to safeguard the U.S. against potential threats that could arise from international arms proliferation.