What is the West? Why does it need to be defended? From what, by whom, and how? These are thorny questions that international society must grapple with in order to meet the security challenges of the 21st Century. This little book provides answers to these questions. In it, James Gow sends out a clarion call for a radical re-interpretation of the right of self-defence within the terms of international law and international politics. The world is a wonderful, but dangerous place. There are any number of threats to peace and security, ranging from new forms of terrorism and the proliferation of weapons of mass destruction to environmental degradation, famine and disease. Defending the West matters to everyone, regardless of colour, creed, or nationality. It matters to those who are seeking to destroy it as much as it does to those seeking to protect it. Defence of the West requires pre-emptive action, but it cannot be undertaken on a unilateral basis and outside the law. Instead of outlawing pre-emptive action, we must acknowledge that it is necessary and ensure that it can be taken in a framework of partnership and legitimacy.