We should disarm all the nukes in the world and just hold a yearly gladiatorial fight where each country contributes either one or a team of 3 fighters (not sure on which would be better). Anyways, the fighters battle it out in a big forest or desert and there are weapons and things scattered throughout. They also jump out of a plane and a minefield zone is established. Additionally, they'll have a collar with a bomb that will go off if they don't move to the center. It will be broadcast live and donations go to charity.
Basically PUBG but with real people and winner gets money and his country gets stuff like favorable trade deals.