NATO had played a paramount role in defending the independence of its member states and providing security and stability in Europe. NATO is a cornerstone of European security and a solid transatlantic community of shared values. Warsaw block's and Soviet Union's disintegration marked the end of Cold War and evoked the emergence of radically new geopolitical situation in Europe. Indubitably, facing new realities, NATO could not remain unchanged.
Allies rapidly realized the necessity of NATO's role's and policy's profound transformation and started process of adapting Alliance to the new geopolitical situation. At the NATO 1990 London Summit Allies admitting that the West and the East were no longer adversaries recognized a distinctive role of the Alliance as an "agent of change". Since, early 1990's the Alliance, while retaining its core function of territorial defence assumed the new function of collective security, which itself required the creation of new institutions and putting forward new initiatives. Following the principle of collective security NATO launched the historical "Partnership for Peace" initiative and linked it with Alliance's further enlargement. Creation of the North Atlantic Cooperation Council (NAC C) and its transformation into Euro-Atlantic Partnership Council (E APS), targeting new tasks and missions, emphasis on non article 5 activities, elaboration of a radically new strategy, reflected in the new Strategic Concept which was issued in 1991 and adapted in 1999, engagement of Russia and paramount role in peace support operations in Europe have been showing NATO's ability of adapting to the rapidly changing contemporary realities, its practical use and crucial role in enhancing peace and stability. At the same time, since the end of Cold War a lot of opponents of the NATO's existence have been emerged.
They argue that as the East-West confrontation is not already taking place and so NATO has no strategic enemy, there is no necessity to keep the Alliance, which as institution of Cold War is already an anachronism..