Rejected petition Governments of the world should to affect arrest of dictators accused of committing crimes against humanity & ethnic cleansing

Invading a country to effect regime change may be justified in certain circumstances, as military intervention in Libya indicates. The criteria of when to effect regime change should be worked out amongst NATO, EU & UN members. Perhaps agreement by any 2 of these 3 well recognised, prestigious international institutions would suffice for governments to effect regime change against a country. Perhaps the criteria for effecting regime change should be (1) to depose a dictator with overwhelming evidence of committing crimes against humanity towards its citizens (2) a head of state who refuses to step down after being overwhelmingly defeated in a general election (as for Mugabe of Zimbabwe, Laurent Gbagbo of the Ivory Coast, General Thein Sein of Burma) (c) pariah state with refugees having to flee in hoards in fear of their lives to seek asylum in other countries (d) a pariah dictatorship/undemocratic brutal regime with suspected WMD (like Iraq, North Korea) despite UN resolutions.