Ok apparently someone from the GIGN leaked ON AIR this morning that secret services were somewhat aware of the imminence of an attack.
3 options : either they screwed up hard, and I wonder how this would be possible : if they knew that an attack was imminent it's obviously because their surveillance is very very good
second the guy interviewed is a plain liar (why would he do this and self destruct himself in the process?)
or third government knew, let it happen, sacrificed hundreds in order to switch to urgence state in the country, lockdown the borders and accuse the migrants flux to let terrorists in western countries in order to tell them to gtfo.
You will see in next days what states will say, but i'm pretty sure they will not send troops to kick ISIS' ass and instead happily leave all the migrants from this 70 year middle east mayhem stay in their shit without help.
Of course i'd be very happy to be wrong..