Isolated regional wars over religious ideology are more likely, me thinks. The same pacts and treaties used to drag in countries in WWI & II don't really exist anymore. Religious ideology is also shaky because the movement of combatants and acts are based on cell structure, which in themselves have a lot of autonomy. If you get to the economics and the heart of the money matters to finance this activity & shut it off, you will see a drastic reduction in the "terrorist acts" which target people for what they do, rather than who they are. A war on terror and religious ideology is a doubled edged sword. Its strength lies in the base that it is spread over wide disassociated parts, its diversity of interpretation and is largely conceptual. These are aslo its weaknesses for lack of cohension, structure and leadership. The closest we came to a coherent terrorist state was Afghanistan under the Taliban & Al Qaida - who could have sponsored wars and terrorism as a nation-state, which is still required to prosecute a proper well-run, well cooordinated war.