France does seem to have a deep seated nationalism that I don't understand very well. They care extremely deeply about their cultural works to a degree that does not make sense to me.
"The difference between patriotism and nationalism is that the patriot is proud of his country for what it does, and the nationalist is proud of his country no matter what it does" [0]
That seems like a feel-good post-hoc euphemism (but ok, I accept that language evolves).
Either way: how did France (the nation) make any of these artworks? You could argue it was made by anyone in the spectrum ranging from "the artist" to "the humanity". Stopping at France seems arbitrary and a bit... nationalistic.
If any institution "made" them, it's the Catholic Church, not France.
Given that France is "overwhelmingly Roman Catholic" [0], your last statement could be considered interchangeable. Perhaps (and I'm not French, so I don't know) many of the people consider them to be one and the same. Either way, it's a reasonable point that you made.
Assuming you're American this is the most hilariously ironic comment I've ever seen on HN.
Americans are some of most obnoxiously nationalistic people I've ever encountered. Note: I've lived both in Paris, and also NY and California (14 years in the US). Only in the US do you hear mobs of nationalistic folk chanting "USA USA." I've never been in France or the UK and seen similar things. Think about things like Americans boycotting French Fries and calling them "Freedom Fries" when France decided not to join the illegal and immoral Iraq War.
There's an interesting attitude towards the word "nationalism" in US. As you say, it's probably one of the most enthusiastically civic nationalist nation in the world - indeed, to the point where American sociologists have described it as a "civic religion" at times. But the word "nationalism" itself is almost exclusively interpreted as "ethnic nationalism", and has an unambiguously negative vibe. So people who practice civic nationalism describe themselves as "patriots" instead.
My favorite part of the "USA! USA!" chant is how seriously non-Americans are about it. Every time I've started or participated in a "USA! USA!" chant it was only about 15% nationalism and 85% a joke. Part of its enchanting humor is how that seems lost on everybody else.