Internal affairs of a nation need not be interfered by outside forces. It is an international political code or conduct generally accepted. Russia has involved itself in support of Asad, the ruling government and NATO the people protesting against the government. There is this tug war and there is another side to it, the entire Arab League. And now Syria is in turmoil and so many innocent people have been victims or targets. Can these different strategies help Syria overcome their existing atrocity? Could be there a different wisdom or idea that can help them? Yes the annihilation of ISIS is a common strategy whether Russia or NATO or any outsiders who are for humanity but the raid could be at times wrongly placed and it is likely to do more harm than good. I am concerned, in fact all of us are concerned about it who are watching the goings-on in Syria in recent times.
Says who? No it isn't. A state is usually allowed to handle their domestic problems as they wish, but there is one exception which allows foreign intervention, and that is gross violations of human rights, genocides, atrocities and such.