Foreign Slaves. Was this Immoral ?

Foreign Slaves: Permanent & Involuntary slavery defended!! (Leviticus 25: 44-46)

Atheists claim that Biblical slavery was immoral because: - 

• God commanded Israelites to keep their foreign slaves permanently.
• Foreign slaves became slaves involuntarily. 

What the Atheists do not seem to understand is that the slaves from the surrounding pagan nations mentioned in Leviticus 25:44-46 were those whom Israel were to either drive out or kill. Under the circumstances, slavery was a rather humane option.

The Israelites were restricted to the Ammonites, the Moabites, the Edomites, and the Syrians, who were their neighbours, but were not permitted to buy any slaves from the seven nations who were in the midst of them, and whom they were ordered to destroy (Deuteronomy 20:16-18). When we read the Bible we can see how Israelites fought against them and destroyed their inhabitants.

• War against Ammonites in Judges 10:6-12
• War against Moabites in 2 Kings 3
• War against Edomites in 2 Chronicles 20
• War against Syrians in 1 Kings 20

Israelites bought slaves from foreign slave traders (Genesis 17:12). As we know that Israel's slavery was better than that of other nations so this law rescued foreign slaves from being sold to wicked nations. In fact, Deuteronomy 23:15,  which forbids Israelites to hand over a runaway slave to his master, was given in order to save pagan slaves who ran away from their oppressors and came to Israel. This shows how God desires all men and nations to be liberated. 

One of the reasons why Hebrew slaves were freed was to return to the property of their forefathers (Leviticus 25:41) but in case of pagan slaves, they were sold by their own nations so they probably didn't own any possessions and if they were freed they would surely starve to death or become end to other wicked nations. And we know that Jehovah claimed to be a jealous (feeling or showing a resentful suspicion that one's partner is attracted to or involved with someone else) God.