Cybersecurity and Infrastructure Security Agency CISA

The Cybersecurity and Infrastructure Security Agency Act, signed on November 16, 2018, converted a DHS headquarters directorate into a full operational agency with a clearer mission. It is led by a Director confirmed by the Senate. CISA has little regulatory power over the private sector, which owns most critical infrastructure, and works mainly through voluntary partnerships, alerts, and technical help.

CISA leads the defense of federal civilian agencies' networks, can direct agencies to patch urgent flaws through binding operational directives, and maintains a catalog of known exploited vulnerabilities that agencies must fix. It coordinates with the operators of sixteen critical infrastructure sectors, from power and water to hospitals and banking, shares threat warnings, runs emergency communications programs, and offers free security assessments to state and local governments. Since 2017, election systems have been designated critical infrastructure, and CISA helps state and local election officials secure them.

CISA's work on elections drew partisan conflict after its first Director, Christopher Krebs, called the 2020 election the most secure in American history and was fired by President Trump on November 17, 2020. In 2025 the administration ended CISA's work on election-related misinformation, cut roughly a third of its workforce, and reduced some partnership programs, while a 2015 law protecting companies that share threat information with the government lapsed and was later temporarily extended. It lapsed again briefly in 2026, and the September 2026 stopgap spending law extended it through December 11, 2026. Supporters said CISA had strayed from its core cyber mission, while many security experts warned the cuts left the country more exposed to attacks from China, Russia, and ransomware groups.