Excelant point! God interveaned to save Moses for His purposes.
You did not answer the question. Why did God not intervene on behalf of the rest of the male children?
1. Could God have prevented the shootings but chose not to?
Yes.
Then if it is as you say, that there is nothing in the shootings that glorifies God or serves some other good purpose, you make God out to be a monster, not preventing "senseless" slaughter when He was able to do so. The same would be true of you if you knew what was about to happen, and had the ability to prevent it but did not.
2. Where do you get the idea that He must explain His reasons for anything to you?
The Old Testament. He does not owe me an explination, but He usually provides one.
He sometimes provided a reason for His actions, and often did not. The times that He did were evidently meant for His glory then, before those people. Not all events in His plan are meant for His glory at the time of their occurence, or for those presently witnessing them, but one thing is certain,
all things will and do redound to His glory.
Your point was that God did not ordain these killings because He had not made known to His people the good reason for them. You base that on the idea that He "usually" did something like that in the Old Testament when He ordained destruction? Your premise is unsound.
Meager basis upon which to deny the absolute sovereignty of God, don't you think? Box, you don't seem to see your arrogance. You presume to think that since you can't understand the why of many things it must be that those things are not ordained by God, as though your ability to comprehend is the standard by which God must operate. To mollify your own qualms you invent a God who plays peek-a-boo with Himself to have "plausible deniability". He
could ordain all things, but does not because He
doesn't need to? And because of that indifference senseless acts of evil occur? You are guilty of the same incoherence as Calvinists who claim God "passes over" the reprobate, but actively intervenes on behalf of the regenerate. Both of you can't comprehend how it is that God can ordain evil and hold the perpetrators of that evil responsible while not bearing responsibility Himself. So both of you construct an incoherent paradigm to explain it that in one way or another mitigates against God's omnipotence.
You make God a little less and yourself a little more than reality to accomodate your conceptual limitations, when instead you should let God be
GOD and strive to comprehend that within those limitations. Accept your own limits instead of placing them on God.