I believe that if a country is commiting "genocide", then other countries have a right to go and protect those people. E.g. Rwanda 1994. Within 100 days an estimated 800,000 - 1,000,000 men, women and children were hacked to death with machettes. If the UN had acted on this then far less lives would be lost. But the UN intervening could be seen as an "occupation" or a "war". This is situation where war could be justified.
The occupation of iraq by the British and American forces which was started by the retard bush is a war that cannot be justified. They aint got no weapons of mass destruction but they do have a hell loada oil. All theyre doin there is killing innocent people, as the brits did in the north of ireland in the 1970s/80s and 90s