Such relationships are never equal.
In the "God of War" methodology (Napoleon I) a coalition and set of alliances was recruited in the context of the unification of Europe, but it was always understood that French interests would come first.
In WW2, the interests of the US & British Empire came first over those of France (who fought valiantly in Italy and 1944-45 Europe), Canada, Australia, New Zealand, Free Poland (they took Monte Casino and jumped into the maelstrom at a "Bridge too Far.") etc.
It is always thus. Nothing is "fair." Get that through your heads.
Now we have a coalition among Syria, Russia and Iran to defeat Sunni extremism and preserve the Syrian state as an example of the possibility of multi-confessional governments in the ME.
This, IMO is obstructed by the mindless insistence of the US on the overthrow of the Syrian government. Can it be more clear that this policy, long established by propaganda, is the goal of the hyper-nationalist Israeli interest of "The Lobby" in the US?
The Russians want better relations with the US. They want this to avoid their eventual submission to a junior partner status with China in which the menace of the Golden Horde's repression comes again. (Look it up)
To that end the Russians have (IMO) dragged Syria to a climactic battle in the east at Raqqa . These areas are critical to US goals in the ME but not to those of the Syrian state who must seek to consolidate all the heavily populated areas in western Syria.
Is Russia screwing the Syria government in their own interest? Yes.
Would I welcome a victory of US aligned forces at Raqqa? Certainly. I wish I were there. pl