From Col Lang's blog a piece on Tehrik-e-Taliban, by Richard Sale Direct attacks on Pakistani engineers, scientists involved in the nuke program and Kahuta Research Laboratories seems a pretty dumb tactic. Looks more like TTP lashing out at symbols of state power. If your goal was getting your hands on WMD, you'd want some of the wet wear to be cooperative. This is complex machinery not a couple of tons of Semtex. On the other hand if you just wanted to draw DC into preemptive action it might have its merits. If you actually want the nukes infiltrating the security around the program would be a better idea. As the TTP have obvious links to the Pak military that's a worrying prospect.