| This is a term used by the military to refer to anything that augments a soldier's ability to wage war. Usually an advance in technology, a force multiplier is not limited to a bigger weapon, but can also include improvements in weapons, tactics, and basic equipment that increase the power of an individual soldier to bring the fight to the enemy.
Here are some famous examples:
- The radio., as it allows a single soldier in a remote area to call in artillery fire or an air strike on a target.
- The rifle. By putting a spiral groove in the barrel of a gun, a spin is placed on the bullet, stabilizing it and enabling it to travel farther and straighter, increasing accuracy and range.
- Repeating firearms. For example, until the development of the Spencer Rifle (the first repeating rifle to be issued to the military), an infantryman during the Civil War (unless he was an officer with a pistol) could only fire about 2 or 3 shots a minute. Custer wrote the inventor that he would be willing to attack a force twice his strength if his men had spencers and the enemy did not. I don't think I need to point out how much an impact the gatling gun had on the battlefield.
- The flamethrower. 'nuff said.
- The Higgins Boat It enabled amphibious assaults, allowing masses of troops to be able to attack from ships at sea to the shore.
- Aircraft. The ability to reconnoiter the battlefield from above all by itself was a significant strategic advantage, and the original reason the military adopted airplanes into their order of battle.
- The Tank. Again, I don't think I need to explain the advantages of a large, treaded, armored vehicle with a really big gun to any level of detail.
More recent force multipliers include the laser rangefinder and the laser designator (hell, anything involving lasers), smart bombs, computers, night vision, kevlar, and better uniform designs. Just about any technological advance is reflected in new equipment that better enables a soldier to operate. When it does, it is called a force multiplier. | 
