Re Crimea: International laws forsee referendum as a legal mean of separation. And that is what people of Crimea did.
Re Syria: NATO was bombing in Syria for years and it didn't have (and still doesn't have) any legitimacy to do so - neither by the UN nor by the syrian government. Russia was invited to help by the elected government officials and this has the legitimacy to be there.
Re Syria: NATO was bombing in Syria for years and it didn't have (and still doesn't have) any legitimacy to do so - neither by the UN nor by the syrian government. Russia was invited to help by the elected government officials and this has the legitimacy to be there.