Autodidact
Intentionally Blank
:no:
You need to look at the big picture. The entire book (1 Samuel) is not really about the Amalekites. If you read the read the entire book, you would come to realise it is really about how Saul lost his kingship and all about the rise of David to ultimate power (for a human, at least).
The genocide of Amalekites was only used as a springboard for the story of Saul's downfall and David's eventual kingship. And of the two, God favoured David.
Of course, either way, the poor Amalekite babies are just as dead. But hey, as long as God gets the right king, who cares about a few dozen dead babies?