The Western Economic Supreme Treaty or WEST, is an intergovernmental military and economic alliance which was created on 3 October 2012. The organization constitutes a system of collective defense whereby its member states agree to mutual defense in response to an attack by any external party. WEST's headquarters are in Berlin, Germany, one of the 4 member states across at The Americas and Europe. An additional 4 countries participate in WEST's Partnership for Peace. The combined military spending of all WEST members constitutes over 70% of the world's defence spending. It is thought to be the successor of NATO. It was created as a rightful response to eastern aggression and the formation of the Eastern Alliance Socialist Treaty.