The title of the episode "Tip of the Spear", refers to a combat force that is used to puncture the enemy's initial lines of defense, to be quickly followed by concentrated forces which destroy any remaining threat.
Straps (or Straphangers) - qualified personnel from another unit brought in for a mission. In Tip of the Spear, these were the CIA agents and Clay.
APC - Armored Personnel Carrier.
Mogadishu - The Battle of Mogadishu took place in Somalia in 1993 and inspired the movie Black Hawk Down.
ISU - light-weight containers for cargo.