UNATCO

The United Nations Anti-terrorist Coalition Organization (UNATCO) is a major antagonist organization in Deus Ex. UNATCO are depicted in Deus Ex as a peacekeeping, anti-terrorist organization established to deal with the growing problem of  international terrorism. UNATCO is described as "the world's first ever policemen" UNATCO plays a key role in the storyline of Deus Ex, since they responsible for many evil acts including the dispersal of biological  warfare agents against the general population, and military  suppression of any peaceful or military resistance to UNATCO  member governments. UNATCO's questionable acts are because they are actually a branch of a larger conspiracy, Majestic 12, which is using UNATCO to take over the world.

The game does not specifically mention when UNATCO was formed, however, the player learns that UNATCO has in fact been in existence for many years. For instance, Paul Denton joined UNATCO in 2040. In 2035, Paul Denton is said to have vowed to join UNATCO to fight against terrorism. Mechanical augmented agents, Gunther Hermann and Anna Navarre have also worked for UNATCO for many years, although how long is not made clear in the game. JC Denton confirms that UNATCO itself had existed many years before 2052 (the fictional date where Deus Ex takes place) when he says to Shannon, "...Amazing, if you think about it, all the hours I spent dreaming about working here...". The character, Walton Simons indicates that UNATCO may have been formed by executive order due to an attack on the Statue of Liberty, however, an in-game  document reveals that the executive order had to do with the establishment of the UNATCO headquarters on Liberty Island,  rather than with establishment of UNATCO itself.

UNATCO are introduced in Deus Ex following a false flag terrorist strike on the Statue of Liberty. At the beginning of the game, the player receives his orders direct from UNATCO director, Joseph Manderley. Manderley reminds the player to always and constantly follow procedure. During the game, the player discovers evidence, suggesting that UNATCO is part of a larger conspiracy known as Majestic 12. JC Denton uncovers financial links, which bind UNATCO to the director of FEMA, Walton Simons and key leader of Majestic-12. The player also learns that Joseph Manderley is but a puppet appointed by Majestic 12 to do their dirty work, including sending the player to assassinate  Luminous Path scientist, Tracer Tong. Joseph Manderley was appointed in order to provide an urbane face for UNATCO, but is later assassinated and replaced by Walton Simons in order to "restore discipline". UNATCO are depicted in the game as constantly framing other organizations for various acts, including the bombing of the Statue of Liberty, drug smuggling and  murder, which were done to reduce support for the NSF organization and their allies. UNATCO personnel, especially in the case of the player are rarely allowed discretion, even if the action would improve society. Characters, such as Paul and JC Denton, who use discretion are often heavily rebuked, or even expelled from UNATCO.

As a result of the actions of the player, the global communications network called the Aquinas router is overloaded and destroyed. This plunges the world into a dark age. The organization, Majestic 12 and by extension, UNATCO are depicted in the sequel Deus Ex: Invisible War as having ceased to exist. The UNATCO headquarters on Liberty Island is an effective ruin occupied by a class of people known as bums. With the exception of the ruined complex towards the end of Deus Ex: Invisible War, UNATCO is rarely mentioned, implying that they disbanded after the events of Deus Ex.

When Deus Ex was released in 2000, Ion Storm created a  website (www.unatco.org) for the fictional organization to   promote the game. Ion Storm pulled the website shortly after the September 11 attacks. The motto of UNATCO is from the Sententiae of Publilius Syrus: "Nihil aliud scit necessitas quam vincere", which  means, "Necessity knows  nothing else but victory."