Yes, DNSSEC is used by the United States government, as well as many other organizations around the world. DNSSEC is a set of extensions to the Domain Name System (DNS) that provides a way to digitally sign DNS records, which helps to prevent DNS spoofing and other types of attacks. DNSSEC can be used to provide an additional layer of security for a wide range of applications and services that rely on the DNS, including email, web browsing, and online banking.