In A More Perfect Union, Peter Sagal explores the Constitution’s most striking and innovative feature: its resilient brand of federalism. The framers created a strong national government while at the same time preserving much of the power and independence of the states. This delicate balance of power, seemingly hard-wired for disagreement and conflict, has served America well for more than two centuries. Let's take a closer look at how it has also led to tensions throughout American history and still sparks controversy today over medical marijuana, gun control, and Obamacare.