France finally got its version of 9/11. Killing soldiers and Jewish elementary school children wasn’t outrageous enough. Killing cartoonists and yet more Jews didn’t make the cut either. After all, like Kerry said, killing the cartoonists was kind of understandable and there’s enough anti-semitism to fill volumes (disguised under support to « Palestine » or « jews control the world« ).
Attacks on a chemical plant (one person beheaded), or on a church (one woman shot dead) were not enough to wake up French people. Who cares about isolated incidents? Then there was the infamous Thalys attack, which would have been a massacre save for… American tourists! So it took 130+ dead, hundreds of wounded, lots of orphans, probably some people left disabled, for the French to wake up.

French didn’t know, ignored it, but they were at war way before 13th of November. Not fighting didn’t make it less of a war, it just made escalation inevitable.