The Countering America's Adversaries Through Sanctions Act (CAATSA), enacted as Public Law 115-44 in 2017, is a U.S. federal law that imposed comprehensive sanctions on Iran, Russia, and North Korea to counter their adversarial actions. It consolidated three titles: the Countering Iran's Destabilizing Activities Act, targeting Iran's ballistic missile development, support for Hezbollah, Hamas, and other regional proxies, and human rights abuses; sanctions on Russia for interference in U.S. elections, cyberattacks, and support for Syria's Assad regime, including secondary sanctions under Section 231 on entities dealing with Russian defense and intelligence sectors; and enhanced measures against North Korea, such as banning U.S. financial services to North Korean banks, sanctions on shipping and cargo, a presumption of forced labor for North Korean-produced goods, and restrictions on foreign aid to governments trading defense articles with North Korea. The bill passed the House 419-3 on July 25, 2017, and the Senate 98-2 on July 27, 2017, with veto-proof majorities. President Trump signed it reluctantly on August 2, 2017, criticizing it as flawed and unconstitutional for limiting executive foreign policy flexibility. The law has resulted in designations of Russian entities, enforcement actions by the Office of Foreign Assets Control (OFAC), and international compliance challenges, such as those arising from Turkey's purchase of Russia's S-400 system.