In keeping with Holly West's "I posed a question on Facebook" idea,
What's a good way for a third party to start a war between two crime families?
I've gotten Dashiell Hammett's RED HARVEST, as suggested, and am diving into that.
So, you want to get the two families fighting. You make one think the other one did something. Went to the cops. Cheated. Killed the wrong person. Is about to combine forces with another family or group.
From the Romulans to the Corleones, this has been a big factor in crime fiction.
So you kill a Hatfield and blame a McCoy and let them fight it out. I'm thinking, if you're plotting this out in a story, you would have your protagonist come into conflict with a Hatfield, then have a situation in which he/she kills the Hatfield. Then blame a McCoy, That moves things along nicely. You can raise the stakes after a bit by having the McCoys begin to figure out that your protag is really to blame. Or maybe the Hatfields start to figure that out. More killing!
OK. Red Harvest is a good example of groups going against each other. If you have other examples or suggestions, let's hear them.