Territorial disputes may take the form of disputes over precise boundary demarcations or over the claims of a neighbouring state and a distant, usually colonial, power to a dependent territory. Disputes may also occur in connection with territory contiguous with both states, usually as a consequence of annexation during war by one state of an adjoining region. Conflicting claims exist over certain territories. Should such territories become independent and apply for membership of international organizations, such as the United Nations, difficulties may arise if such claims have not been settled. Claims by states to territorial waters along their coastline also give rise to disputes. In the case of isolated islands, such claims are especially problematic because of the 200 mile territorial maritime zone surrounding each island. Where several countries have claims to such islands, the only sure way to avoid confrontation is for their respective forces to avoid patrolling those areas. This leads to a power vacuum which in certain cases favours the proliferation of illegal activities such as piracy (notably in the South China Seas).
Previous examples of such claims are: Iraq's claim to Kuwait's territory; Morocco's claim against Spain over Ifni; Morocco and Mauritania against Spain over Spanish Sahara; Argentina against the UK over the Falkland (Malvina) Islands; Guatemala against the United Kingdom over British Honduras (Belize); Spain against the UK over Gibraltar; Ethiopia against Somalia over the French Territory of the Afars and Issas; Mauritius against the United Kingdom over Diego Garcia; Japan against the USSR over the islands of Etorofu, Kunashiri, and Shikotan; China, Vietnam, Taiwan, Malaysia and Philippines over the Spratly Islands in the South China Sea; and Turkey and Greece over Crete.
Many grievances and claims were left unresolved following the 1914-18 and 1939-45 wars, as was the case with previous European wars. The opinion of the Polish, Czechoslovak and Baltic peoples was not considered in determining the frontiers of those countries, which were established by agreements between other powers or by annexation. Territorial disputes may disrupt regional cooperation for development or defence - as in the disagreements between Argentina and Chile, and between Turkey and Greece (by which NATO is impacted).
The Antarctic regions constitute a special case in which seven nations have put forward conflicting claims. (These have been set aside for the moment under an agreement which facilitates unrestricted cooperative scientific exploration). A number of islands have been contested, from the Kurile to the Falklands (Malvinas). The seabed, outside territorial waters, is another special case, as are potential disputes over surfaces on the Moon, the planets or their satellites.