The United States has a 7500-mile land and air border shared with Canada and Mexico and an exclusive economic zone encompassing 3.4 million square miles.
Each year, more than 500 million people are admitted into the United States, of which 330 million are non-citizens.
On land, 11.2 million trucks and 2.2 million rail cars cross into the United States, while 7,500 foreign-flag ships make 51,000 calls in U.S. ports annually.
On land, 11.2 million trucks and 2.2 million rail cars cross into the United States, while 7,500 foreign-flag ships make 51,000 calls in U.S. ports annually.
There are over 1 million firefighters in the United States, of which approximately 750,000 are volunteers.
Local police departments have an estimated 556,000 full-time employees including about 436,000 sworn law enforcement personnel. Sheriffs' offices reported about 291,000 full-time employees, including about 186,000 sworn officers.
There are over 155,000 emergency medical technicians who are national registered.