The NATO bombing of Yugoslavia (code-named Operation Allied Force) was NATO's military operation against the Federal Republic of Yugoslavia that lasted from 24 March to 10 June 1999 and brought about the close of the Kosovo War. It was only the second major combat operation in NATO's history, following the September 1995 smaller-scale bombing Operation Deliberate Force in Bosnia and Herzegovina.
NATO's objectives in the conflict in Kosovo were set out in the statement issued at the Extraordinary Meeting of the North Atlantic Council held at NATO HQ on 12 April 1999 and were reaffirmed by Heads of State and Government in Washington on 23 April 1999:
The Yugoslav Government claimed that it was protecting the minority Serbian population of Kosovo against attacks by the Kosovo Liberation Army.
Operation Allied Force relied almost exclusively on the use of a large-scale air campaign to destroy Serbian civilian and minor military infrastructure from high altitudes. Ground units were not used, although their use was threatened near the end of the conflict. This approach was adopted to minimize the risk to the NATO forces and attracted considerable public criticism due to its relative ineffectiveness against mobile ground targets such as tanks and troop formations. Strategic targets such as bridges, hospitals and factories were also bombed, particularly in the later stages of the conflict. Long-range cruise missiles were used to hit a number of heavily defended targets such as strategic installations in Belgrade and Priština. Civilian installations such as power plants, even water processing plants and the state-owned broadcaster were also intentionally targeted.
NATO's bombing campaign lasted from 24 March to 11 June 1999, involving up to 1,000 aircraft operating mainly from bases in Italy and the aircraft carrier USS Theodore Roosevelt stationed in the Adriatic Sea. At dusk, F-18 Hornets of the Spanish Air Force were the first NATO planes to take off to bomb Belgrade and perform SEAD operations. BGM-109 Tomahawk cruise missiles were also extensively used, fired from ships and submarines. The United States was, inevitably, the dominant member of the coalition against Serbia, although all of the NATO members were involved to some degree — even Greece, despite publicly opposing the war. During the ten weeks of the conflict, NATO aircraft flew over 38,000 combat missions. For the German Air Force (Luftwaffe), the mission was its first conflict participation since World War II. In addition to air power, one battalion from the US Army's 82nd Airborne Division was deployed to help combat missions. The battalion secured AH-64 Apache attack helicopter refueling sites, and a small team forward deployed to the Albania/Kosovo border to identify targets for Allied/NATO airstrikes.
The proclaimed goal of the NATO operation was summed up by a NATO spokesperson as "Serbs out, peacekeepers in, refugees back". That is, Serbian troops would have to leave Kosovo and be replaced by international peacekeepers to ensure the Albanian refugees could return to their homes. However, the summary had an unfortunate double meaning which caused NATO considerable embarrassment after the war, when over 200,000 Serbs and other non-Albanian minorities fled or were expelled from the province. It was also suggested a small victorious war would help give NATO a new role. Terms like "humanitarian bombing" and "humanitarian war" were employed by the politicians.
The campaign was initially designed to destroy Serbian air defences and high-value military targets. Bad weather hindered many sorties in the early stages. NATO had seriously underestimated Milošević's will to resist: few in Brussels thought the campaign would last more than a few days, and although the initial bombardment was more than just a pin-prick, it was nowhere near the concentrated bombardments seen in Baghdad in 1991 and 2003. On the ground, over 300,000 Kosovo Albanians had fled into neighboring Albania and Macedonia, with many thousands more displaced within Kosovo. By April, the United Nations was reporting that 850,000 people — the vast majority of them Albanians — were refugees that fled from Kosovo. Another 230,000 Albanians were listed as internally displaced persons (IDPs) who had been driven from their homes, but were still inside Kosovo.