The enclave of Trenton is actually located on the remains of Newark, New Jersey. When the enclave was formalized, the civic leaders decided that if they took the name of the state capital, they would have sovereignty over the entire territory. As the only major enclave in the former state of New Jersey, they more or less got their wish. The population mainly consists of descendants of people who were living in New Jersey at the time of the cataclysm, but there is also a large population descended from people who were able to escape New York City.
Trenton is run as an oligarchy and as a business. At any given time, the thirty most successful business owners direct policy for the enclave. Usually, the bulk of them are shareholders in either the docks or manufacturing. The interests of the oligarchs are counter-balanced by the Trenton Citizens' Union, which has a nonvoting seat on the council.
Trenton's biggest export is trade. They have the largest working docks in the country and are one of the only places on the East coast capable of trade with the other continents. They also have a large manufacturing sector, which does sometimes produce surplus goods. Their third biggest export is mercenaries. Trenton has a large and well trained standing army as a substitute for natural defenses and veterans who retire from it often go on to work as mercenaries or as officers in the militias of other cities.