hi thinker,
if i ever went in the path of Allah and was given a slave from the spoils of war then islam commands me to treat this slave kindly and justly.
i cannot hit him on the face, i must dress them in the same standard of clothes i wear, feed him the same food, give him a bed and room simular to my own, and work him no more than i work myself.
yes he is a slave as he is 'owned' and in this it is simular to the slavery of the west, but only in this respect, in everything else it is totally different, subhanallah even if i hit a slave unjustly they have a right of complaint to the qadi (islamic judge) who if they feel it was unjust can order their freedom.
now you may or may not agree with the principle of slavery but it is part of the deen of islam which i accept absolutely as it is from the Quran and Sunnah and therefore no muslim if he / she understands it is from the Quran and Sunnah should question this.