I had, some time ago, the desire to apply to a research position in the CNRS or INSERM, [both] French research associations. I have discovered that it would be almost impossible to get such a position in France when it looked promising in the USA. Why is it so?
My impression is that most of these research positions are jealously kept by the French faculties for their own students or their friends' students. That's the main problem you have if you leave the country and stay for some time in the States, because you lose the contacts you may have with the French faculties.
Many of my friends who stayed in France and did a PhD had some chances to join the CNRS, when my French fellows who got a research education in the States keep struggling to get this chance; and it is not a matter of research skills.
...