Lipo-Flamethrower

The Lipo-Flamethrower is exactly what its prefix suggests: a flamethrower fueled by fat. And not just any fat: human fat. This brilliant new weapon/peacekeeping device/beehive remover connects, by means of an ingenious suction tube, to the user's butt, midsection or thighs, eliminating the need to carry around a heavy tank of incendiary fuel. At the pull of a trigger, fat spews forth from the user's reserves and is jettisoned out of a nozzle, bursting into flame in the process and striking fear into all who witness the act.

This "weapon" will, in fact, end war and cause world peace. This is because of the following events which will occur after the Lipo- Flamethrower's invention:

First, dominance in war will shift to the world's most morbidly obese countries: Samoa and Nauru. However, all the fat people of the world, after being drafted to their countries' respective armies, will soon use up their fat in combat, thus solving the global obesity problem. Afterwards, the now-incredible difficulty of waging war without fat people will lead all countries to give up war entirely, leading to peace. Eventually, however, people will become fat again and the cycle will begin anew. Alas...!