With the new century, DISA faced even greater challenges as a DoD service provider. Preserving radio spectrum, information assurance, ensuring interoperability, and establishing secure wireless links were just some of the tasks performed by the agency. Perhaps the most significant achievement of the agency in 2001 was its immediate response in the aftermath of the attacks of Sept. 11, 2001. DISA justified $300 million in supplemental funds to support the Global War on Terrorism by providing critical communications paths and command and control enhancements for warfighters.