Well and good in the 50&60s when these Fuckers didn't have a way to get here. It's an interconnected world now. When you have a parasitic dictatorship that feeds by keeping its population enslaved, and by controlling its media brainwashes them into believing the Western World is responsible for their depraved conditions, the hate that foments now ends up here in the form of terrorism.
I see what you are saying, but I think the situation is a little more insidious regarding Islamic fundamentalism. it has nothing to do with people's living conditions. Heck, Osama Bin Laden himself was a pretty wealthy businessman if I remember correctly. It has nothing to do with economy and everything to do with an aggressive ideology which seeks nothing but world domination.
Another thing is that the "military industrian complex" (I know, I know...) loves the current situation. Hard to justify an ever expanding military budget after the Cold War finished. This "War on Terror" is very useful to some interests. It's not about actually solving problems, but about perpetuating problems. If they wanted to solve the problem there are some unpopular but highly effective measures that could be taken (think Hiroshima over the Islamic State). I am not a wacko, by the way. Simply a realist. The reason Hiroshima and Nagasaki happened were because they were the only reasonable measures to guarantee a swift end of the war.
I say do something like that to the Islamic State. Give civilians a 2 day warning to clear the area, and have heavy aerial presence around it to make sure the "bad guys" don't run away en masse.
But solving the problem quickly is not what the armament companies want, obviously. They want an extended conflict that will guarantee a steady source of income at the expense of a steady stream of blood.
There are also internal political measures (highly unpopular amongst some sectores perhaps) that could be taken. For example, immediately deporting every family member (immediate family) of American terrorists. That would make family members more vigilant and willing to report possible problems with people in their environment to the authorities. Sure, some innocent people would be kicked out, but when you are confronted with a problem with this magnitude there are no "perfect" and "clean" solutions.