If engineers could pursue nuclear power free from influence and interference, then I would have full confidence in their ability to create safe systems. Unfortunately politics and other forces have a way of always intruding.

Feynman's analysis of the Challenger disaster, and of the engineer who stayed up in the middle of the night refusing to sign-off on the launch in the face of commerical and political pressure ought to give anyone pause. In fact he was able to cite the exact reason for failure that occured - gaseous breach of the O-rings, due to operation outside design paramters. The fact his career was also finished, is the icing on the cake.

Chernobyl(cumulative maintenance procedural failures) and Fukushima (concrete walls too low to withstand the Tsunami) also stand as evidence that science and engineering doens't exist in a vaccum and always gets co-opted.