Five years after 9/11, there's still costly wars in the Middle East both with regards to casualties and money. Added to the never-ending struggles are the activities of al-Qaeda and bin Laden who are still channelling money and troops into these conflicts.
- Insurgent troops(in Iraq and Afghanistan)are still being recruited from Muslim schools in Pakistan, Iran and other places.
- The families of suicide bombers are still being reinbursed by wealthy financiers.
- Weapons for private armies(like the Hezbollah)in the Middle East have been traced back to Iran and Syria.
- The training and indoctrination of troops in "Terrorism 101", probably still continues around the world under the leadership of al-Qaeda leaders.
The great poverty and dispair in the Middle East is a breeding ground for the creation of willing Mujahedeen(Holy Warriors).
The oil money and organizations are there to continue these wars and sap the economic strength of the Western Nations.
In any great conflict cutting off the supply lines of the enemy is essential to defeating it. Again, this is dealing with the sources of terrorism and not just the effects.
http://en.wikipedia.org/wiki/Al_Qaeda (History Of Al Qaeda)
http://www.csmonitor.com/2006/0911/p10s01-wogi.html (The Goals Of Al Qaeda)