On 4 April, 1949, twelve free countries decided to set up the Atlantic Alliance in order to maintain peace and security, foster stability in the area covered by the North Atlantic Treaty, which was under threat from Soviet expansionism, and provide the means and the machinery to promote cooperation among member states. NATO, which today consists of 16 nations, has stood for over forty years as the shield which has given Europe the longest period of peace in its thousand years of history.