In your opinion, do all people have at least some basic measure of worth or value?
If not, is it permissible to kill without further justification those people who do not have at least a basic measure of worth or value? Why or why not?
If you believe all people have at least some basic measure of worth or value, why do you believe that?
A starting value at least, such that one should respect another as one would expect to be treated. Their subsequent actions then tend to determine how that respect is upgraded or downgraded. But we all have some measure of worth or value, if not for us then to others usually.
The second question hence is not really on the cards. Who am I to judge others? The railway switch test of morality has always bothered me - saving numbers over deliberately killing one. (If I did this, I would wreck the points just as the train was going over them and thus save both parties by derailing the train at the junction, lol)
The last point - we don't get to choose to be born, or that with which we are born, disregarding our environment and subsequent upbringing, so why would I judge others so carelessly. I do believe worth is inherent in the larger majority unless there are particular circumstances to say otherwise.
I couldn't really say whether it would be right to kill Hitler for example as there really are just too many individuals all throughout history where much the same could be proposed for lessening the harm they cause.