Zero Sum analysis has long dominated Washington policy debates, where it is most prevalent in economic projections. The dynamic nature of the private economy is ignored when setting tax rates or making fiscal projections, as it is always assumed a dollar added in one place will have to equal a dollar subtracted somewhere else. It spills over into trade and industrial policy as well, where hands are wrung over a "declining" industry while myriad new industries are springing up all around us.
In the post-Cold War joint world, Zero Sum thinking has hit the Pentagon hard. Why should the Navy have significant air power when we have an Air Force that should be handling that? Why do we need airborne intelligence, surveillance, and reconnaissance (ISR) capabilities when we can do that mission from space? Or why should the Army have organic fires when the Navy and Air Force can handle those missions for them?