"Somewhere between 750 and 850 women were given trace amounts of radioactive iron in a “cocktail” drink during their pregnancies by health officials they trusted. Dr. Paul Hahn, the lead researcher behind the experiments, claimed that the study was intended to record the absorption of iron during pregnancy.
However, in the years since, many pundits and journalists have theorized that these experiments were a part of a military study to learn about radiation exposure. "

It was no doubt both, considering what was happening and at stake at the time, both us and the Nazis were working on nuclear bombs, they had no idea of what the effects of using them would be, how else were they supposed to find out? They had to know.

The fate of humanity depended on our scientists learning what we needed to learn. I had a professor in college who during the war did extensive research with LSD sponsored by the government. He did all sorts of crazy experiments we could never do today on airmen and mental patients but that is why we know about LSD and the effects of air pressure on pilots at different altitudes and the effects of different steroids.

"Vanderbilt spokesman Wayne Wood told the Washington Post that all of the files were destroyed by the research team in the 1970s."
This was almost the most heartbreaking part of the story, after all that the subjects unknowingly sacrificed they destroyed the data.

These things would be unethical to do today because we don't have to do them, because we already did them to find out what would happen.

Now compare that to the modern day paradigm of drug companies killing hundreds of thousands of Americans annually with known side effects from properly prescribed drugs and you have a much more important conspiracy than some old WW2 radiation study.