Islam ( as well as other religions) gives people a message of hope and a desire to live in a better world. But when the believers can’t understand the forces that are bringing changes around them ( such as the activities of multinational companies, the use of foreign military might,…), they get confused. Because many have lost faith in the political parties to help them out, they turn to what is familiar to them : their religion, which they understand traditionally. Hence, cultural and religious isolationism is their way to affirm their identity, fundamentalism their way to fight liberalism, capitalism.
Since ever, some Muslims have considered “jihad”( literally holy war) as the sixth pillar of Islam ( I have already written a post about the other pillars of Islam), although it has never been elevated to this status. The concept of “jihad” was the basis for the early expansion of Islam and was carried out very much in the literal sense of the word. ( A similar concept underpinned the Crusades of Europe’s Christians in the mediaeval times.)
Many of the attitudes surrounding western perceptions of Islam are based on fears as to the wider implications of the concept. On the other hand, the word actually derives from an Arabic root meaning basically “to strive”, and many Muslims emphasize a less literal interpretation in terms of a personal spiritual striving against sin to attain greater closeness to Allah.