Jetrel, VOY 1
Turns out Neelix has a backstory after all. His family was wiped out in a Hiroshima-like blast and there he is, meeting Robert Oppenheimer.
There are some reversals, revelations, moments of interest but the main thing is this: are scientists to blame for what politicians and Generals do? Probably, yeah, maybe a little. This is the first time I liked Neelix.