This selective tallying of body counts is rather hypocritical. When the right talks about the number of people killed by illegal immigrants, the only response by the left is that Americans kill more Americans than illegal immigrants. Which is true but if we're going to talk about bloody hands and preventable deaths then let's be fair and objective and criticize anyone who has blood on their hands or did not even at least make an effort to prevent needless deaths.
In the view of many on the right, the blood of Laken Riley, Jocelyn Nungaray, et al is on Biden's and Harris' hands. They were unwilling innocents whereas the three people killed in Iran were willing soldiers. This is what soldiers do and they know the potential for combat is always there when they sign up.
They had the choice not to go. They may have been court martialed for it but they had that choice nonetheless. Instead, they went because they knew it was what they signed up for. Riley, Nungaray, Morin and the others had no choice.