That is a fair question. How to answer questions like this is why there different forms of Judaism. For example, Orthodoxy believes the Temple will be rebuilt & the animal sacrifice restored. For them, killing an Amalekite, if 1 existed, would be obligatory. The Reform believe the Synagogue replaced the Temple. Similarly, the command of the Prophets later in the Bible to love thy neighbour outweighs the command to kill. The prophetic emphasis on God as a universal God, rather than just the God of Israel, makes him God of the Amalekites (if any) just as much as God of the Jews. So the question is, is Judaism a religion of set immutable laws that must be followed come hell or high water, or is it a philosophy such that the spirit of the law changes as people change in their understanding of themselves, each other, & their God? We have seen that Orthodoxy & Reform have 2 very different answers to this question. My own answer is in the middle somewhere. Some would call me a Conservative Jew. I prefer to avoid