The way I see it is this: There are 3 major world powers on Earth right now that are expansionist to some degree with their ideologies. The top dog is the United States, which while doesn't take any territory for themselves, prefers allies that are in alignment with their economic and political goals. The second is Russia, which has a long history of empire building, and because of their unique geographical location of their capital, needs to have large buffer zones to protect themselves from invaders. The third is China, which has always been a private and powerful country, but has grown economically, and thus politically and militarily as a result.
And so, regardless of whoever is right or wrong, the three are just going to compete. The US has a recent, but strong history of distrust with Russia, and the two are at the point where they compete over allies. Why do you think Syria is such a big deal for both countries? Because if Syria is stable, they become an oil outlet for Iran, which is a competitor to Saudi Arabia.
So, it's about the money. Follow the money and you understand the motives of the three.