Nationalization is when something that's been privately owned switches to being controlled by the government. In the United States, airport security went through nationalization in 2001, becoming a government agency.
Nationalization is often viewed negatively in countries with capitalist economic systems, seen by some as a slide toward socialism or communism, in which nationalization partly serves to redistribute money among all citizens. At various times in the US, nationalization has occurred in areas like the railway system, utility companies, and banks. The Latin root word is nationem, "birth, origin, breed, or tribe," and the original meaning of nationalization was "the act of investing with a national character."