It's also one way to have the entire sorry episode of french collaborationism and the Vichy sell-out dragged out into the open again. This is exactly what anti-Semitic france doesn't want the world to be reminded of -- the fact that they helped the nazis exterminate the Jews. Many of those collaborators are still alive and Le Pen will be certain to introduce this in a trial.
I'm not sure I want the French reminded of how anti-semitic they still are. The French are hardly rational as a culture. They'll probably do something stupid.