Whataboutism already.. impressive.
What people really should be talking about (those who actually read the article) is this:
French prisons auditor critical of what it called “disparate” and tentative measures hastily put in place, which offered “unsatisfactory” responses to the unprecedented phenomenon of radicalisation in French prisons.
Three things:
Power
One thing that always happens after major attacks is the government seeks more power and is almost always given some if not all of what it asks. People are more worried about justice than them losing their own rights without seeing it. Now saying that no laws should be put into place or the PC crowd only wanting to be insanely light with how things are handled is moronic but so it putting a democratic society on a path to be "democratic."
Sanity
One thing American, Russian, and Chinese prisons have in common is they're all shit in one way or another. Forced labor in one, quick executions in another, or clean new prisons but the prisoners are confined for 12 hours a day like in the US for petty infractions in prison.
France is none of those. French prisons are not the best in the world, but they aren't that - yet. Citizens learn to not care or maybe they do care but they want them to be confined for murdering their son, daughter, etc. But I assure you that confinement is not the solution. With that said, I don't think France is confining these people like the US, I think it's more along the lines of segregation which I see nothing wrong with in this context.
Correction
A problem every American is well aware of is the lack of correction in American prisons despite them being 'Department of Corrections'. You don't purge terrorist ideology from prisoners by isolating them.. and again I agree with what France is doing, to an extent. But there must be some sort of balance. By simply throwing all of these terrorist together, away from the rest of that prisons society - you're doing the same thing ISIS and other terrorist cells brainwash them with "you're not one of them, you never will be."
I believe it's in the best interest of the French people to pour a substantial amount of money into serious counselling for these individuals and gradually put them back into general population, not isolate them indefinitely. And this draws on yet another topic - people not wanting their tax money going to terrorist of all people while France suffers from massive unemployment and an uncertain future.
TL;DR: It's a very complex situation where there's no "yep, agree with that.. nuff said, next article" - One thing ISIS and other terrorist groups do is they brainwash these people far more efficiently than any Western radical group (KKK for example takes years or decades, ISIS takes a few months to radicalize someone) into thinking that they dont belong with their home society, they dont love them, they dont respect them - but ISIS does, ISIS is filled with brothers that love each other and only work in the name of Allahu. So isolating a bunch of people that're brainwashed that way only reinforces that. Many of the arguments made against Gitmo can be made here.. Gitmo goes far beyond the torture aspect, if you don't believe me - listen to those that actually were freed from there. Isolating a bunch of terrorist together only radicalizes them even further.