This is Jerry Goldman again, the principal author of Chapter 4, "Federalism." In this chapter, we shall explore the allocation of power between the states and the national government. The allocation has shifted with the passage of time. It never remains constant and it tends to shift directions when we least expect it.

The response to Hurricane Katrina is a good example of the failure of federalism. This horrific storm was beyond the capacity of state and local officials to address. They were either unable or unwilling to give up their authority to the national government. And the national government was uncertain--at least at the start--whether this was an issue that fell within its constitutional domain. Let me focus on fivekey points to bear in mind as you navigate this chapter.

First, federalism is really about the allocation of power between a central government and its constituent parts. And while the chapter explores two key theories of federalism t, the bottom line is that theories are less important than politics. As politics and policies change, so does the allocation of power, that is, so does federalism. Second, the national government's power tends to expand during periods of great crisis, such the Civil War, the Great Depression, the battle for civil rights, and the war against terrorism. Does that power ever contract, and if so, under what conditions?

Third, every branch of government has some say in the shifting power line between the central government and the states. The early Supreme Court of Chief Justice John Marshall empowered the national government in its fledgling period. But Marshall's successor, Roger Brook Taney, reversed course, shifting power to the states with, some say, devastating consequences. Can you explain what those might be? Congress plays a vital role in power allocation. And it has the means to do so. How has Congress leveraged its power to expand national power at the expense of the states? Are there any limits to the expansion of such power? What might those be?

Fourth, when you think about the shifting nature of federalism, you should consider whether such shifts are consistent with pluralism or majoritarianism. Take the case of Iraq. It has chosen a weak form of federalism that comes very close to a confederation. Some power is vested in the central government, but the regions and factions seek to control their areas and resources.

And, fifth, federalism imposes dual loyalties: to that which is local and to that which is national. Within such dual loyalties, the two contrasting federalism theories (dual federalism and cooperative federalism) tend to support either limited or enlarged national power.