Why can't we regrow limbs/organs like lizard/sea-stars?

There are some animals, such as hydras and earthworms, that can regrow body parts even if they are chopped in half. More complex organisms usually lack the ability to regenerate lost body parts. Salamanders are the noticeable exception.

However, their ability to regenerate is limited to limbs and tail. In the 1960s Stanford scientist Victor Chandler Twitty conducted some experiments to test the ability of newts to return to their annual breeding sites. One of things he tested was to remove the eyes of some of the newts.

Amazingly, the blinded newts not only survived, but they were able to return to the same stretch of stream from which they were born. These blinded newts were unable to regenerates their eyes of course. There are experiments that show that the lens of a newt's eye can be regenerated, but these experiments did not completely remove the eyes, just the lens, unlike Twitty's experiments.

Usually regeneration is limited to the most easily and frequently lost in battle...limbs and tails...not the other parts, organs or systems.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.