i don't think that "islamism" has a single source, but i don't think it's much of a reaction to zionism, either. the dominant force was probably soviet influence. the soviets were fundamental in organizing states in syria, iraq and elsewhere that were based on a concept of "arabic socialism". as in other places (east asia, africa, south america), the kremlin felt it was necessary to inject an ethnic component into the struggle in order to build greater solidarity. this isn't very socialist, but it happened.

the americans reacted to this by training mujahideens in afghanistan with saudi capital. this is the more direct source of the islamism we see.

counterpunch carefully straddles the line of anti-semitic conspiracy theory, and i've long been cautious of it. the articles they post often give the impression that they were written by jew haters that are toning down their language and rhetoric for polite consumption. this is one of them.

and i'm stating that from a perspective that is highly critical of israeli ethnic nationalism (i think this article does get the point right, despite it's wonky attempt to put islamic terrorism on the long list of crimes perpetuated by jews).

http://www.counterpunch.org/2013/11/04/israel-and-the-dangers-of-ethnic-nationalism/