The Vatican is the smallest nation-state in the world with an area of 108.7 acres. It is located in the heart of Rome, on the west bank of the Tiber River. According to 2004 estimates, its population numbers some 1,000 people of various nationalities; most are the families of Vatican City employees and cardinals of the Roman Catholic Church. The Vatican maintains full sovereignty over its territory and population. Its citizens hold dual citizenship: that of Italy and that of the Vatican. Latin is the official state language, whereas Italian is the commonly spoken tongue. Like all nation-states, it issues stamps and mints currency; it funds refuse collection; it maintains a fire department, a police force, and a small army. The Vatican's revenue derives from public contributions and investments in real estate, bonds, and securities. Its secretary of state oversees foreign policy matters and its diplomats enjoy full immunity. As of...