Back in the day the test site was an amazing place. Not only did they set off a number of A Bombs, they also worked on a number of other projects. I knew a number of engineers and research folks who worked up there. They were very interesting people, but never talked about what they were doing. However, over the years things leaked out, not only about the nuclear rocket engine but also bunker busting bombs, extremely powerful guns.....not for artillery, but shooting projectiles at very high speed to study how other materials reacted when shot at those speeds. As for the rocket engine, it was radioactive, but if used on a second or third stage after getting out of Earth orbit, I can see where it would have been very successful. Anyway, I guess they are now pursuing other means of propulsion such as ion power. Anyway, the heyday of the test site was an amazing time, on the forefront of science and researech.
Dan Markoff