The importance of physical and political geography to international politics is self-evident. The influence of climate, access (or lack of access) to resources, national agricultural potential, and similar factors have an obvious influence on the development of polities. It would, for example, make no sense to discuss Icelandic history without reference to the facts that Iceland is an island, was accessible to Vikings in longboats, and today is strategically significant to any polity that wishes to control access to the Atlantic.