Back in the '80s, I guess it was, maybe the '90s, some in the US were talking about areas of Los Angeles, New York, etc., being essentially "no-go zones" for police. It was one of the reasons for setting up quasi-militarized SWAT units: the "bad guys" had more firepower than the "good guys." When responding to a robbery they'd face gunfire from people not necessarily involved in the robbery itself, just defending their turf. It didn't need to be frequent to have a "chilling effect."
And, yes, "no-go zone" was the word used, along with "off limits". Both in the press when said by mayors or police chiefs as well as in tv shows and movies.
This bit of Americana wouldn't have been salient enough to stick in the minds of French observers to be remembered 20 or 30 years later, who take offensive without realizing we said it about ourselves before we said it about them. (Or that this had been said about them quite convincingly several times in the last decade, most notably when they had the quasi-riots in some of the banlieux a number of years ago and the police had to pull out, barely patrolling some areas during the day and not at all at night.)