It must have been about fifty years ago when I was at a formal gathering and chatting to an Australian Army Officer of about my age who was attending the military School of Languages..
At that time, the iron curtain was still in place and the Chinese nation was beginning to flex its muscles militarily, leading to a feeling that world war might not be far away.. A joke of the day for those learning languages was that optimists learnt Russian and that pessimists learnt Chinese. This officer said to me that he thought both camps were wrong, and whilst we might have some smaller localised conflicts, in his view WW3 would be a re-run of the Crusades.
Like me, he will have been long retired, and if he is still around, he might get some grim satisfaction from David Cameron's warning that "Britain and the West face a decades-long battle against Islamist terrorism in North Africa."
In fact there was a series of Crusades, starting in 1071 when the Byzantine army was defeated by Turkish Muslims with the result that Christians were denied access to Jerusalem. This led to a series of Crusades against the Muslims, these occurring mainly between 1095 and 1291, a period of some 200 years. It was not one continuous war, but a long series of battles with various Muslim leaders trying to take or re-take territory in different parts of the Middle East.
Reading about the crusades, one is struck by the similarity with the events taking place now, with Christianity being driven out of the Middle and Near East by Muslim forces. There are no decisive battles that could be called a victory, and when defeated, the Islamic forces just move their efforts elsewhere, in which could end up as a long running conflict
Regrettably, I think that for once David Cameron is right. We clearly need to stop the spread of Islamic terrorism before it becomes a genuine threat to this country. In many ways, what happened in Algeria and what is happening in Mali, Sudan, Somaliland and Northern Nigeria, presents a far greater threat to this country than Sadam or Afghanistan ever did. Don't forget that much of the Iberian peninsular was occupied by the Moors for centuries, and they still regard it as their territory.
Time will tell what happens, but I don't think any of us alive today will see the resolution of this conflict, if indeed it is ever resolved.