Was the NATO bombardment of Serbia legitimate?

After the disintegration of the Socialist Federal Republic of Yugoslavia, Kosovar Albanians became targets of the Serb policy of "ethnic cleansing". UN requested both parties to the conflict to stop hostilities and to return to negotiations. However, peace negotiations between the Federal Republic of Yugoslavia and Albanian Kosovars failed in Rambouillet in France in February 1999. Indeed, Slobodan Milosevic rejected the peace plan for Kosovo. In face of the inaction of the Security Council, NATO forces began an aerial bombing campaign against Yugoslav military targets on 23 March 1999. The campaign ended on 10 June 1999 with the withdrawal of Serbian forces from Kosovo. This intervention was justified as being a humanitarian intervention against Serbia to protect Kosovar Albanians from life-threatening risks.

[...] The bombardment of the Serbian Radio-television in April 1999 for example was very controversial since it caused the death of 16 employees. Examining all these criteria, we can affirm that it was rather legitimate for NATO to intervene in Kosovo: it was justified on moral grounds. Indeed, the international community could not allow atrocities to be committed anywhere. Moreover, the situation in Kosovo had the potential of spreading conflict in Europe. However, the bombardment had too many disastrous consequences on Serbia: destructions, refugees’ flows . [...]

[...] However, this official justification of NATO intervention was not the only one. It was, why did NATO not intervene against Ankara to defend Kurds in Turkey or in Rwanda to prevent the Tutsis genocide? So there were other reasons for NATO to intervene. This war was mainly an American war, supported by the European allies. So the aim of these bombings was to consolidate NATO influence in this area and to weaken Milosevic’s regime, which was an obstacle for the foreign American policy. [...]