When I was in college, I always found it very impressive just how much a single group of college students with a low amount of funds could actually get done. From building planes that actually fly to robotics that I couldn't begin to describe, they do amazing things as a part of senior projects, or just for the fun of doing them. Now, skip over to "terrorist" groups, who have a much larger fund basis, more focus, and more manpower. I don't see why they don't have working missiles.
Rocket science is just that, a science, and with the right minds you can produce just about anything. Heh, maybe I should shut up before the next project of the evil-hearted is to steal our college students and use them to build super-neutron bombs against us!!
MB