The Kyoto Protocol is a fantastic example of voluntary international cooperation to solve the global issue of environmental destruction. Since no nation is forced to participate, it is not a violation of national sovereignty, and since environmental destruction affects the entire planet, which means every nation, Kyoto is an important step in the right direction. Only a coordinated, international effort will be able to make headway in protecting the environment for everyone.
As communications advance, the world is getting smaller. The things that one nation does affect other nations. In order to be responsible citizens on a planet with diminishing resources, it is necessary to come to agreement over behaviors that we collectively deem harmful. A law does not take away a person's freedom. A law establishes a minimum standard of behavior expected of the citizenry. A person is still free to do whatever he wishes, but there are consequences for his actions. The concept of sovereignty in light of agreements such as the Kyoto Protocol is the same. A nation may continue to act in any way it sees fit, but there are consequences. Such is the price of living in a global village.