God commanded the Israelites to go to war and, in order to accomplish victory in that war, eliminate every man, woman, boy, and child.
God didn't command us to do anything immoral. He commanded the Israelites to go to war and take the land that was theirs. He also commanded them to do whatever was necessary to take that land.
*sigh* As I said, it's tedious to repeat stuff.
Here's what God said:
Now go and strike Amalek and utterly destroy all that he has, and do not spare him; but put to death both man and woman, child and infant, ox and sheep, camel and donkey.
Does it say do what is necessary to win? Or does it say to be sure to kill every child and every infant?
In Numbers 31, the war was over. The Israelites had already won. Victory was not at issue. They had victory. It's not about victory. Forget victory. They already had victory.
They fought against Midian, as the LORD commanded Moses, and killed every man. 8 Among their victims were Evi, Rekem, Zur, Hur and Reba—the five kings of Midian. They also killed Balaam son of Beor with the sword. 9 The Israelites captured the Midianite women and children and took all the Midianite herds, flocks and goods as plunder. 10 They burned all the towns where the Midianites had settled, as well as all their camps. 11 They took all the plunder and spoils, including the people and animals, 12 and brought the captives, spoils and plunder to Moses and Eleazar the priest and the Israelite assembly at their camp on the plains of Moab, by the Jordan across from Jericho
Victory was not at issue. The war was over. But they forgot to kill the babies!
"Have you allowed all the women to live?" he asked them. 16 "They were the ones who followed Balaam's advice and were the means of turning the Israelites away from the LORD in what happened at Peor, so that a plague struck the LORD's people. 17 Now kill all the boys. And kill every woman who has slept with a man, 18 but save for yourselves every girl who has never slept with a man.
It had nothing to do with victory. The problem was, winning wasn't good enough--they neglected to commit genocide, which angered God, so he sent them back to be sure to kill the boy babies and take the virgins captive.
You condemn it because you have a predisposed hatred of it.
I admit it. I hate genocide. Also killing babies. It just bugs me for some reason.
God is the definer of morality. Something is only moral/immoral because God labels it as such. Therefore if God tells us that something is immoral, then it is immoral. If God tells us that something is moral, then it is moral.
(emphasis added. I will have more to say about this later.)
So if God commands you to do something which otherwise would be heinous and reprehensible, it's moral, because God commanded it? So, for example, if God commanded Israelite soldiers to kill newborn male infants, that would be a moral action, for you? (And in fact He did command just that.)
God tells us the He does not want us to take lives.
Except when he orders us to.