People complain more when it gets done by Muslims because Islamist terrorism is an unmatched global problem right now. Or at least so the media reports lead everyone to believe.
Is it always justified? Probably not. But when was the last time an incident took place outside of Israel that could even remotely be termed as 'Jewish terrorism'? Or for that matter an incident outside of India that could be called 'Hindu terrorism' or 'Sikh terrorism'?
I guess it's just that such Muslim ghettos have a higher chance of producing violent extremists than ghettos of any other community. As to why that is, is another issue.
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