I always thought Benzema's remark about how he's French if he scores and Arab if he has problems was interesting. It's obviously not unique to him, I'm pretty sure others have said it about their situation, too. But the interesting part is that there's obviously also a flip side. Psychologically, I am sure it's also much easier to feel French when things are going well than when things are going badly. Footballers are performers. Performers live off the approval of their audience. What happens when you lose, don't score, get into trouble? Approval turns to criticism.
If you stand there hoisting a World Cup trophy for France and the masses cheer you adoringly, it'd be almost inhuman not to feel elation and unity. If things go badly, then the problems come up and differences are played up. It works both ways because not only can France reject Benzema, Benzema can also reject France - at times. As someone who is a migrant himself - I can say that the relationship between a migrant and an adopted country is more like a marriage than like a family relationship. There's ups and downs in both types of relationships, but family has a finality and inevitability to it that a marriage doesn't, so there's always more of a 'base' connection to family.
The thing that makes the Benzema case (and the corresponding Ozil case) so politically loaded really is that neither is a migrant. Benzema born in France, Ozil born in Germany. These types of complexities are supposed to decrease with the generations born in the country to migrant parents, but instead they persist and sometimes get worse. Football has at times tried to act like it's the solution to that problem, but I think it's a fabrication.