You are ignorant of what the speck in your eye is. Go away and learn the teaching.

So you would kill all the adults and leave the babies to die a slow agonising death or for animals to kill?

You need to wake up to yourself... Do you think no babies killed in any war by Man.
Didn't they kill the babies themselves? Didn't mankind have not care for their children. Didn't they sacrifice their Children to Molech

Leviticus 18:21
Verse Concepts
'You shall not give any of your offspring to offer them to Molech, nor shall you profane the name of your God; I am the LORD.

God destroyed the nations who were already teaching to offer their children as sacrifices to idols/false Gods.
The truth is God hated such things and he destroyed completely those nations so they could not lead the Israelites astray.
In the parts of the bible, the parts where Nations are destroyed or even Pharaoh and his armies it is all about Nations who kill children and even mistreat others.

God actually was putting an end to such things by destroying Nations who did this.
He was just and allowed no nation who harmed their children or could harm the children of other nations to exist.

God told the Israelites that there was to be no child burnt offerings etc.
But the evil was such that they did it. Googled these for you.
Read through them... God hates child sacrifices. By destroying nations and their descendants he put an end to it.

As you can see witchcraft and Paganism were the original cause of Children being sacrificed to false Gods.
God put an end to those nations and punished the Israelites if they failed to obey his rules about their children.
Now go away and stop bringing up something you have no understanding about. God hates the killing of Children and killed those who did it, and their descendants so they could not do it again.

The truth has shown how you are the one in denial.

The book shows that God does not want the things man makes up for himself.
It was man who decided to sacrifice his Children.
Abraham showed a faith that knew God could bring his Son back from the dead.
The same Faith of Abraham that saw Christs coming. It also shows that God did not want and does not want the children or people of others sacrificed to him. Would you promise God to sacrifice a person to him?
Mans nature is the evil part...

Jephtah’s daughter

Having been told they must not make human sacrifices what does Jephtah do?

He promises to sacrifice the first thing that greets him. Prepared to kill another person then his only daughter is the first.

He tells her and she agrees to fulfill the promise. A promise wrongly made doing that which God does not want.
But he is taught a life lesson he will never forget.
A lesson to us all that God does not want us to make sacrifices of humans.

Now you know that the truth is these people who were destroyed along with their descendants were about ridding the world of such evil things as sacrificing their children. These people were not civilised they had no police stations and no one to stop them killing their children. It is that part of it's history modern paganism has left behind. They made blood sacrifices of their children and people.  So the truth is God destroyed in mankind that which was not good. He killed off those who killed their children and the Children as they would have only carried on the same practice.

Now the truth is out you can shut up! Because you were wrong all along. God killed those who killed their children and their children to stop more being killed.