Chemical - If any planet were to survive - one would guuess - physics.
Congress holding UFO hearing Tuesday morning at 9 AM EDT: Watch it live here!
Not at first there wouldn't be a war. Both sides would most likely corporate for the best possible outcome in getting to the planet. Once the first voyage returned and ships begin to leave Earth to settle the new planet is when the war would begin, if any war were to happen at all. The only way that a war would begin is if the greedful corporation's associated with religion such as T.V. Evanglical's decided that they wanted the planet all to theirself so their belief's were the accepted reality of the planet then the Chinese would most likely be attacked enroute citing "natural" causes such as a machine failure or spacial phenom's destroying the transport ships. The Chinese might try the same thing citing that the reason for the loss of the Americans transports was because their God(s) didn't want them leaving Earth in first place so Karma was sent into the void to exact the Earthen Gods revenge on the Exodusing humans.That would be the start to Star Wars! China and the west would be competing to get there first. In order to make sure the other side doesn't reach it first the annihilation of the other side would be the first task.
In the meanwhile I would improve my secret stargate and claim the planet for myself