Professor Mary Ellen O ’ Connell, The Art of Law in the International Community (Cambridge 2019):
”In 1999, US President Bill Clinton and his Secretary of State, Madeleine Albright, wanted no more Rwandas or Srebrenicas on their watch. Thus, with the willing support of the UK ’ s Prime Minister Tony Blair, they were able to rally all NATO members to support a 78-day bombing campaign of Serbia to attempt to end persecution of Kosovo’s majority ethnic Albanian population. The campaign had no Security Council authorization. Only Belgium argued it was lawful as an humanitarian intervention. The USA gave no offi cial legal justifi cation for a major use of military force for perhaps thefi rst time since the adoption of the UN Charter. An estimated 20,000 people died once NATO bombing started in contrast to dozens killed in the crisis in the previous year . No plan for mass killing of Kosovars was found.” s 133
”NATO engaged infi ghting for the first time during the Kosovo crisis, which had nothing to do with collective self-defence of its members. The war not only violated the UN Charter, it was ultra vires the North Atlantic Treaty. […] NATO also engaged in the 2011 Libya intervention, plainly exceeding the terms of the authorizing Security Council resolution, Resolution 1973, but also the limits of necessity and proportionality.” s 169