The National Defense Authorization Act for Fiscal Year 2021, named after William M. (Mac) Thornberry, is a bill that sets policies and authorizes funding for the Department of Defense and other related activities for fiscal year 2021. It covers various defense-related areas such as procurement of military equipment, research and development, operations, and maintenance. It also addresses personnel policies, healthcare, and responses to COVID-19. Additionally, the bill includes measures for national security programs at the Department of Energy, financial intelligence, anti-money laundering, and counter-terrorism financing. It also reauthorizes the Coast Guard and addresses maritime and homeland security matters, as well as issues related to veterans affairs, communications, and technology.