What should be done about the wealth gap? I know of no practical solutions.
The best way to deal with cancer is to avoid cancer causing agents - and with terrorism the biggest causal agent is the wealth gap.
Perhaps the US should impoverish itself to raise the standard of living in the third world? Perhaps the Arab world should try communism, hoping to even out the wealth gap in their own countries. Look how well that worked in the USSR. Perhaps they should allow the Western democracies to run their countries and straighten out the mess. We could help them and make a profit doing it. This latter idea would probably work, but there is no chance of it being done.

Perhaps some of the root causes of Arab/Islam inspired terrorism is that the Arab cultures are basically neurotic if not down right psychotic. Their treatment of women has got to result in a smoldering anti-male attitude. Boys raised by women who resent men has got to cause psychological problems. A child bonds with his mother at a very basic instinctual level. Seeing her mistreated by the father and by society creates emotional conflict. While mothers have an instinct for bonding with their children, I would expect most of their emotional support to be directed toward daughters. Young children are very perceptive when it comes to emotional issues. A son who feels that his mother favors the sisters, cannot be content and is prone to neurosis.

Some of the problem is likely due to the typical desire of politicians to maintain their positions of power and wealth. I do not think that Arafat ever wanted a peaceful settlement with Israel. If peace broke out, he could expect lees (if any support) from the other Arab countries. If he were responsible for running a government, he would be held to a stricter accounting of money spent and services rendered. He could easily end up losing his position to somebody else, which is unlikely in the midst of on ongoing conflict.

Some of the problem might be due to an inferiority complex pervading the Arab world. They are a third rate tenth century peasant culture with a small percentage of affluent and educated people. They produce little or no modern products. They have little or no research facilities. They do not have a highly ranked college. They have a vague awareness of past grandeur in a non-technological world which no longer exists. Prior to modern communications technology, they were not so aware of their inferiority. Now they know they are an inferior culture and it hurts.