What could happen if, say, a small island off of the coast of Africa became overnight the most powerful country in the world? Can we predict what would happen? Would the world's superpowers be nice and invite the small island nation to the world leader meetings and play nice or would they not like not being the strongest countries in the world and threaten and try to steal the technology of the small island nation?

By most powerful, they are 50 years ahead of any other nation in terms of technology. Technology such as fusion power plants, energy shields, and railguns are commonplace. Bombing or invading the land is pretty much impossible. They have metal storm guns set up everywhere on the island to stop nukes and other missiles or paratroopers. Railguns and predator drones are set up to deal with any hostile ships. Undersea mini-drones armed with torpedoes are set up to deal with any submarines or any undersea threats. The island nation is 100% self-sufficient and is heavily militarized. They build everything from the ground up, and they have mastered undersea mining to supply their needs.

They are interested in being a part of the world. If the world refuses to let them be apart, they will respond violently. They will not share their advancements with anyone and no one from a different country is allowed on the island.