Lots, and lots of Jews and a nuclear power plant just off the coast.
The Port of Miami is known as the "Cruise Capital of the World." It is home to 17 cruise ships, and has the largest year-round cruise fleet in the world. The Port also handles more "megaships" - vessels capable of transporting more than 3,000 guests - than any other port in the world. Carnival Cruise Lines, Norwegian Cruise Line, and Royal Caribbean International all operate exceptional cruise vessels from the Port of Miami. In fiscal year 2000, more than 3.3 million passengers used the Port.
Airline flights from all over the world converge to fill the cruise ships. A hit on the cruise lines, is a hit on the airlines, a hit on tourism, and related industries (food, liquor, etc.) not only for the US but for all the countries they visit!
In fiscal year 2000, the Port of Miamis estimated impact on the community was $8 billion and 45,000 jobs. Miami is in the top ten container ports in the U.S. The Port of Miami has more than 40 shipping lines calling on 132 countries and 362 ports around the world. Of these, 26 carriers serve 33 countries and 101 ports in Latin America and the Caribbean (LAC).
We also have an abundance of asian and german ships that are not reflected in the online statistics but that I have observed in my daily drive by on the way to work. Some of the wealthiest people in the world have homes on the islands adjacent to the port. And, lastly, Miami's financial district, 10 minutes from the port, is a substantial hub for Latin America/US banking.