The myth of the perfect victim.

I was reading about the Amistad once and how the slaves brought from their homelands were kept in deplorable conditions. What stood out was the defence of the captors which said that the slaves too practiced slavery back in their lands.
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Hence it wasnt so bad that the same was done to them. This was rather apocryphal and exaggerated at best and had no bearing on the case so the slaves were freed.
Similar mindset exists now as well.
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Muslims should be faultless victims if they are to complain about injustice done to them. Otherwise something some Muslim did hundreds of years ago, or thousand miles away or something they did themselves can be brought against them as whataboutery.
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This argument is disingenuous. It is disguised as "self-correction" but its timing and nature classify it as victim-blaming and in some cases outright hatred. Once you look for perfect victims you will start a chain where nobody is faultless.
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and so the oppressor you want to defend will be exonerated in your eyes. The victims would be maligned and thats all you would have achieved.