WI: The British Empire, French Empire and Russian Empire enter the American Civil War - Alternate History
By an act of ROB The British and French side with the CSA, while the Russians with the US. Also by act of ROB all can get land forces to North America....
Like this, but not entirely stupid
The British look at the ACW as a wonderful opportunity to cut the US down to a more manageable size, and manages to acquire some allies in doing so. We'll say France and Prussian Germany and their immediate vassals.
They come to this conclusion in May, and start the process of gathering allies and supplies in June of 1861. The plan is to reinforce the CSA directly and also build up forces in Canada. The goal is a CSA thats independent, as well as "negotiating" other potential territory away, say on the West Coast.
The American goal is the same as it was, preservation of the Union. With similar political will as original. Things can change as a reaction to the situation.
Nobody is mindlessly marching to the hilt, but neither is anybody giving up easily. This goal for Britain and friends will take priority over most of what happens in the Balkans or the Ottoman empire. If anything happens.
Well, what do you think happens, and what are the longterm consequences up to 1950?