[mywittyname]

But the post you replied said, they want this to happen because it helps recruitment.

It's only a logical fallacy because you've decided to ignore the predicate statement ("this was a strategy for recruitment") and focus on the implication of it ("extremist groups supposedly want exactly this to happen").

The crux of the OP's argument is that aiding in the recruitment of ISIS is not in the best interest of the French, yet that's what this policy is doing.