The other major "contradiction" potentially unreasonable by liberalism is the one posed by nationalism and other forms of racial and ethnic consciousness. It is certainly true that a very large degree of conflict since the Battle of Jena has had its roots in nationalism. Two cataclysmic world wars in this century have been spawned by the nationalism of the developed world in various guises, and if those passions have been muted to a certain extent in postwar Europe, they are still extremely powerful in the Third World. Nationalism has been a threat to liberalism historically in Germany, and continues to be one in isolated parts of "post-historical" Europe life Northern Ireland.