Security at the embassy is seen as a priority for Ireland 's national police , the Garda Síochána , and is protected around-the-clock by a team of armed , plainclothes detectives from the Special Detective Unit ( SDU ) , the force 's counter-terrorism and counter-intelligence section . They provide close protection to the ambassador and high-ranking diplomats when travelling outside of the embassy , as well as motorcade security . The U.S. Ambassador 's Residence ( Deerfield Residence , Phoenix Park ) is also guarded . Within the embassy and residence grounds , security is the responsibility of the Bureau of Diplomatic Security ( United States Department of State ) and Marine Corps Embassy Security Group , who are heavily armed . Following the September 11 attacks in 2001 , new secure entrances , guardhouses and blast walls were installed . The external windows of the Chancery building are reflective , as a privacy measure . In late 2013 , significant upgrades were made to the physical and perimeter security of the embassy , designed to reduce the threat of vehicle bombings and to repel intruders . This was part of U.S. government security directives at diplomatic missions across 14 different European nations in response to the 2012 Benghazi attacks
September 11 attacks
September 11 attacks
Embassy of the United States, Dublin