From my reading it appears to me that NATO has never initiated a war but only reacted to conflicts already happening? Is this interpretation correct? I find it important to answer as many pro-russian sources claim NATO to be an aggressor, but I have the complete opposite impression.

The list of NATO operations (List of NATO operations) indicates that NATO never started a war but only intervened.

Also List of wars 1945-1989 does not indicate that NATO has ever started a war.

I'm not interested if members of NATO have started wars themself (e.g. US did) but if starting a war was ever part of a NATO mission.

Since many comments are about what consists starting a war. I would suggest to use the term aggression prevalent in international relations.

"(a) The invasion or attack by the armed forces of a State of the territory of another State, or any military occupation, however temporary, resulting from such invasion or attack, or any annexation by the use of force of the territory of another State or part thereof,
(g) The sending by or on behalf of a State of armed bands, groups, irregulars or mercenaries, which carry out acts of armed force against another State of such gravity as to amount to the acts listed above, or its substantial involvement therein.

Definition of Aggression, United Nations General Assembly Resolution 3314 (XXIX).

Following the definition of war by Oxford dictionary:

"a situation in which two or more countries or groups of people fight against each other over a period of time."


  • Comments are not for extended discussion; this conversation has been moved to chat.
    – MCW
    Commented Mar 3, 2022 at 10:27
  • Wars of words are also a situation where people fight against each other... there are lots of wars of words, which precede physical wars, much like street arguments. So why is politics similar to street arguments? Why isn't there a parliament for the world instead of an assembly? Some kind of argument mediation issue is still failing, clearly. Commented Mar 3, 2022 at 18:11
  • The " List of wars 1945-1989" doesn't show who started any wars. Only who won and who lost. Commented Mar 29, 2022 at 19:01
  • @Fizz Why should the 2003 invasion of Iraq be listed as a NATO operation? Commented Mar 29, 2022 at 19:19
  • 2
    "I would suggest to define starting a war as the party which physically escalates first." So what should the US have done after 9/11? Blow up some non-existent sky scrapers of Al Qaeda? Or what should have Israel done after Oct 7? Send some Mossad squads to randomly kill some civilians in Gaza? Your idea that whoever uses more military means "started" a war is just your opinion. There's generally not much history of winning a war [conventionally] without using more military force than the adversary. The only exceptions are guerrilla wars won by guerillas by waiting out the other side. Commented Feb 13 at 10:22

3 Answers 3


There are four main NATO "operations" that can be interpreted as starting a war:

You could argue that none of these events were NATO starting a war, however. The Bosnian War and Kosovo War were already in progress when NATO intervened. In Libya, there was a civil war before NATO intervened. Finally, in Afghanistan, you could argue that the war started when al-Qaeda launched the September 11 attacks.*

Or you could interpret these as NATO starting a war. For example, the Kosovo War started as a low-level insurgency that escalated into a full-blown war in part because NATO threatened military action. In Libya, NATO attacked government forces although the mandate was only for a no-fly zone. In Afghanistan, al-Qaeda was not part of the government; the government was the Taliban, and the invasion was because the Taliban refused to extradite Osama bin Laden.

So it's up to your definition. If the answer to your question is "yes", one or more of these four operations will be the example you seek; if none of them satisfy you, then the answer is "no".

*This is the only time article 5 of NATO was ever enacted to date.

  • Comments are not for extended discussion; this conversation has been moved to chat. Please direct all further comments there.
    – T.E.D.
    Commented Mar 4, 2022 at 14:27
  • 4
    The invasion of Afghanistan was not a NATO operation. NATO as an organization became involved only later through the ISAF mission. So while this can be considered a case of (NATO members) the US/UK starting a war, it cannot be an example of NATO starting a war. The triggering of article 5 is a red herring, as while that led to a number of joint NATO operations, the invasion of Afghanistan was not one of them. This makes about 1/3 of this answer irrelevant.
    – TimRias
    Commented Mar 4, 2022 at 15:18
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    NATO did not start any of those conflicts. They interfered in existing conflicts as an organisation, which is rather a shady use of the organisation but isn't the same as starting a war.
    – jwenting
    Commented Mar 14, 2022 at 9:50
  • Well, according to NATO "By the beginning of April 1999, the United Nations High Commission for Refugees estimated that the campaign of ethnic cleansing had resulted in 226,000 refugees in Albania, 125,000 in the former Yugoslav Republic of Macedonia (1), and 33,000 in Montenegro." That's about 15% of the present day pop. of Kosovo. And it's a bit more % than have fled from Ukraine, abroad. Blaming NATO for the ethnic cleansing started by Milosevic is a bit ridiculous. Thanks to Russian hardliners like Putin having become more influential, Yugoslavia & Russia rejected a SFOR type arrangement. Commented Mar 29, 2022 at 19:46

NATO was created as a defensive alliance to counter possible attacks from the Soviet Union in 1949. Its member states may have fought in wars as shown in your list: List of wars: 1945–1989. Your interpretations are correct because some sources claim NATO was aggressive because NATO's operations was a violation of the International laws by having targets that resulted in the deaths of civilians.:

  1. NATO bombing of Yugoslavia resulted in the deaths of civilians and the destruction of infrastructure. The event was well known for the bombing of the Chinese embassy that lead to the death of 3 Chinese citizens. However, NATO's intervention was caused by the Serbian government bombing Albanians in Kosovo, NATO's intention was to act as a humanitarian intervention.

NATO's operations were focussed on anti-terror and enforce blockades or no-fly zones on specific nations and providing humanitarian assistance. The operations were responses to actions by other nations but not started by NATO itself therefore NATO hasn't started any wars.

  • 21
    I'm not sure stating humanitarian (or whatever) reasons and calling it 'intervention' rather than 'war' (khm...) is a good technical defense. There was a civil war (re Yugoslavia), and then NATO (precisely as an entity!) attacked, despite not being a party initially. One may see it justified, but it's still starting a war (in its proper sense)...
    – Zeus
    Commented Mar 2, 2022 at 0:21
  • 7
    @Zeus what you describe seems to be "joining an existing war", not "starting a war".
    – Dreamer
    Commented Mar 2, 2022 at 7:45
  • 20
    Nobody goes to war without claiming to have the most noble and justified reasons for doing so and nobody goes to war without claiming the other part started it.
    – Regicollis
    Commented Mar 2, 2022 at 12:16
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    @Regicollis, NATO's actions were undoubtedly a violation of international laws but if NATO hadn't intervened, the Yugoslavian government was bombing civilians and committing war crimes. NATO's actions of bombing civilians can be considered a war crime as well but the war wasn't started by NATO. Commented Mar 2, 2022 at 13:33
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    According to this logic, Russia didn't start this war, only intervened to protect Donbass separatists from the Ukrainian government, like how NATO intervened to protect Kossovo Albanian separatists from the Serbian govt. Note I'm not endorsing this logic, only pointing it out.
    – Eugene
    Commented Mar 2, 2022 at 17:48

The members of NATO have started numerous wars that were not under the auspices of NATO itself. Your question could be read as asking about wars led by the organization itself, or wars started by its member countries.

For example, there was much overlap between the countries that invaded Iraq in 2003 and the members of NATO, although the organization itself did not get involved, because not all members supported it.

  • 4
    "I'm not interested if members of NATO have started wars themself (e.g. US did) but if starting a war was ever part of a NATO mission." Commented Mar 5, 2022 at 0:24
  • 1
    Also France and Germany opting out (not only Norway and Belgium and Luxemburg) is somewhat significant.
    – Jan
    Commented Mar 14, 2022 at 11:31

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