As for your last question, about the cause of France's discomforts, the first question is whether France's discomforts are really any worse than Germany's or Ireland's, or America's.

And if they are, perhaps it is because France, an international leader since--as mentioned above--Charlemagne, has not yet figured out her position in the 21st century world.

America sees herself (rightly or wrongly) as the single super-power. Britain has seen a 50 year long collapse of her Empire. Germany has been crushed twice in one century. The Islamists have a mission to protect, defend, and expand Islam. Etc.

But France has on the one hand maintained her independence and leadership position throughout the 20th century, but on the other hand looks forward to an expanded Europe where she represents only about 14% of the expanded Europe by both population and area--not a "controlling" majority of the EU and certainly not a majority of the even more radically enlarged EU that is (or was) on the horizon. The original European arrangement between Germany and France has receded into the distance as the size of the EU has grown.

Also, France's culture is indeed special, but with the Euro, the McDonald's restaurants, the American movies, the German beer, the Japanese cars, the English football "tourists," etc., it becomes difficult to maintain that culture. Does France feel under pressure from all sides to conform to a homogenized European culture?

Maybe this helps explain why the language issue is so important to France, and why it is so important to maintain the special* French economic model: They are symbols of power that must not be allowed to leak away.

* I don't buy into the idea that the French model is so special, in case that's not obvious...