Did those scientists have much choice about joining the Nazi party? And, once in the US, didn't some of them contribute significantly to the NASA space program? Why the hate then?
It's controversial. A lot of old science comes from abhorrent backgrounds. Life consists of various shades of grey. A lot of "the enemy of my enemy is my friend" happened during the following Cold War.
Possibly something to consider as well is that a) under virtually no circumstance would these people ever have to face trial, because rocket scientists are a valuable commodity, and b) the US/USSR were already nudging themselves into the Cold War before the Germans surrendered. If the USA didn't nab these scientists, the USSR certainly would have. I see it was mentioned in the reddit post you linked as well. Another thing to consider, is it would be much easier for the US to keep tabs on these people if they were brought to the US and employed in government jobs than if they went to the USSR, or Argentina like many other Nazi officials.
The US deliberately hid their involvement in some absolutely horrendous crimes - von Brown oversaw a facility where tens of thousands of people were murdered - so they were not prosecuted for war crimes. There were plenty of people in the US who could have replicated the work, but they were so worried about the Soviets that they let some truly monstrous people go totally unpunished to get ahead