Deuteronomy 21
Marrying a Captive Woman
(10) When you go to war against your enemies and the LORD your God delivers them into your hands and you take captives, (11) if you notice among the captives a beautiful woman and are attracted to her, you may take her as your wife. 12 Bring her into your home and have her shave her head, trim her nails (13) and put aside the clothes she was wearing when captured. After she has lived in your house and mourned her father and mother for a full month, then you may go to her and be her husband and she shall be your wife.
Obviously the actions described above would not be deemed acceptable by the majority of Christians living today, nor would the majority of this forum's users see this as acceptable behaviour. It is therefore the case that the opinions and standards of the Christian church have changed over time, and I wish to propose that the same has happened within the Islamic faith.
Rather than seeing the renewed translations (which you describe above) as 'deceptive' euphemisms designed to mask the sinister intentions of bloodthirsty Muslims, it would surely make more sense to assume that the Arabic translators who 'have softened the Koran' did so in order to better reflect the views of today's Muslim community, who would genuinely prefer to 'put the unbeliever away' from themselves, rather than destroy him?