Any country or region that adopts a strategy of reducing its dependence on world or regional trade or on economic and military alliances may be isolationist. It may not take any role in the deliberations of international organizations, although nominally it might be a member. It may not honour previously signed mutual-defence treaties. In another sense, an isolationist policy is one that results in the world knowing that a nation or region has no other interest than its own. It pursues this unswervingly, manipulating whatever international interactions it has to serve this end.
The USA, between the two world wars, was isolationist; and this contributed to the failure of the League of Nations. The Republic of China in Taiwan has elected a degree of political isolationism by only maintaining diplomatic relations with a limited number of nations. There are many kinds of isolationism and many degrees. The word has also been associated with Eurocentric attitudes, particularly in the EEC/EU.
The countries of eastern Europe during their period of socialism were isolated from the mainstream of world civilization.
Individual political communities may indeed enjoy a high degree of culture and civilization. They may have a large and industrious population, an advanced economic structure, great natural resources and extensive territories. Yet, even so, in isolation from the rest of the world they are quite incapable of finding an adequate solution to their major problems. The nations, therefore, must work with each other for their mutual development and perfection. They can help themselves only in so far as they succeed in helping one another. That is why international understanding and co operation are so necessary. (Papal Encyclical, Mater et Magistra, 15 May 1961).
If a nation were to succumb more or less deliberately to the temptation to close in upon itself and failed to meet the responsibilities following from its superior position in the community of nations, it would fall seriously short of its clear ethical duty. When the West gives the impression of abandoning itself to forms of growing and selfish isolation, and the East in its turn seems to ignore for questionable reasons its duty to cooperate in the task of alleviating human misery, then we are up against not only a betrayal of humanity's legitimate expectations, betrayal that is a harbinger of unforeseeable consequences, but also a real desertion of a moral obligation. (Papal Encyclical, Sollicitudo Rei Socialis, 30 December 1987).