There is if you believe this article in Grist. I don’t think using words like “war” and “battle” are really helping the discourse between the two groups, though. I agree that there will be more competition for federal and state dollars, and those political debates could get heated. In the end, though, I think as long as cities continue to become more lively, attractive places, their populations will increase. They will win the “battle” by default. We’ll see, though. I might be too optimistic.