Marines for small wars and the Army for big wars is grossly oversimplified and a terrible construct in my opinion to design force structure. Several other aspects must be considered, one of them is the duration of a conflict, whether big or small. Another thought, while war is far from being an anachronism, but we have many security interests beyond war that will require the military to develop new capabilities that have little to do with war. Furthermore we are pursuing a strategy of engagement and deterrence to hopefully avoid, but more realistic, reduce the occurrance of war. All of these should impact force design. Furthermore the bifurcation of roles for what type of war each service should be designed to fight tosses our joint doctrine out the window. I suspect we'll see the services advocate for specific service roles that may be illogical in an effort to protect budgets instead of doing the right thing which is designing the right joint force capabilities. The Marines clearly have some unique capabilities that will likely be employed several times between now and 2030, but one of them is not a unique capability to fight small wars.