In Homeland Security, the player must defend from multiple waves of enemies, including infantry, APCs, helicopters, and Predator drones. On Veteran difficulty, there are 141 enemy soldiers, two BTRs and three helicopters.
There are many buildings the player may take cover in. The player has many weapons to protect themselves with. There are a few sniper rifles they may pick up at the beginning of the level, one of which has a Thermal Scope, and a few claymores to place around the map. There is also a sentry gun near the sniper rifles that may be setup. There are three more sentry guns in different buildings (on the rooftop of Nate's, inside the diner and the bank), adding up to four in total. There is also an Ammunition Crate on top of Nate's diner, and another in the front of the diner next to the Nova Gas Station (to the left when facing the street at the front entrance).