76. This enforcement tool is not perfect -- any more than the tool of banishing merchants from the medieval trade fairs was perfect for the development of the Law Merchant. See Paul R. Milgrom, Douglass C. North, and Barry R. Weingast, the Role of Institutions in the Revival of Trade: The Law Merchant, Private Judges, and the Champagne Fairs, 2 Econ. & Pol. 1 (1990) (describing the use of banishment and other enforcement mechanisms prior to the rise of the state). Individuals intent on wrongdoing may be able to sneak back on the Net or into a particular online area with a new identity. But the enforcement tools used by legal authorities in the real world also have limits. We do not refrain from recognizing the sovereignty of our territorial governments just because they cannot fully control their physical borders or all of the actions of their citizens.