Without the Shedding of Blood There is No Remission of Sin

[SteveII]

Your reasoning is off. If a hypothetical situation does not have to align with reality, then the answer would also not align with reality. Of what value would the question and the answer be? 

The same value as every other hypothetical. You're imagining a situation to see how you would behave within that scenario.

Now, you might not think that hypothetical can occur within reality, and that's fine, but it doesn't mean that there's no answer, or nothing of value one might glean from it- in this case I'd suggest it'd give us a more comprehensive view of what you value within your moral worldview, which is instructive in a discussion on sin and god. I really can't imagine why theists are always so unwilling to engage with this specific hypothetical- and always in this specific, evasive way- other than that it presents a really bad image problem for y'all.

I know that neither answer to this question allows your beliefs to come out looking very good, but that's not the same as there not being an answer.

Except if I believe, in this case a command from God for me to kill a baby, cannot happen in reality (not possible), then it follows that such a command--even if it was very clear to me, would in fact not be from God. So, what would I be answering? If I say no, what I really mean is that God did not issue the command. I would 100% assume I was mistaken. 

Now, if the question was if I lived in ancient times and a soldier, would I carry out the order, I don't know. In the context of a theocracy and having seen the things a person at that time would have seen (see note below), I could imagine a scenario where it was clear to me that God's judgement on the Amalikites was to be complete. 

NOTE: Other context for the time--

1. Being led by a pillar of cloud by day and fire by night
2. Crossing the Jordan on dry ground
3. Seeing the walls of Jericho fall inward all at once
4. Pagan religions (which included child sacrifice) was to be judged in the harshest possible terms.
5. The Amalikites have been singled out (in Deuteronomy) since long before the Israelites got to the promised land.
6. It was firmly believed that land was promised by the one true God and events have been supporting that belief.
7. All the people groups currently occupying the promise land had plenty of notice to move (they were not murdered in their beds). 

Not to change the subject, but I find it ironic all outrage of possibly killing a limited number of babies in the OT in a very specific context when we as a society have killed hundreds of millions--largely for convenience--and it does not phase those same people.