The purpose of this thesis is to counterargue Simon Dalby’s claim that the national security perspective should be replaced by a global security perspective. Dalby argues that the national security is inappropriate to capture the current issues regarding the environmental security. To counterargue Dalby’s claim, I represent the national security perspective by using the perspective of states’ energy security, and compare current trends and issues regarding states’ energy security and the environmental security. This is done to argue that states can either chose to enhance their own energy security or the environmental security. Prisoners' Dilemma is then used as a theoretical framework on an explanatory example to provide insights about a dilemma, called the Energy- Environment Dilemma in this thesis, that curbs states’ ability to commit themselves to the cause of protecting the environmental security. The explanatory example used is the strategic importance of the Northwest passage for the U.S. and Canada. The results of this thesis suggests that the national security perspective, in combination with Prisoners’ Dilemma, is useful to provide insights about the Energy-Environmental Dilemma. Replacing it with a global security perspective would be to ignore a perspective which can provide insights about a challenge for states to commit to the cause of protecting the environmental security.