I find way more interesting the football pre-Bosman. Small countries could grew a good generation and make a run in Europe, and they could retain most of the talent longer due to the restrictions. It is impossible today.
How they were treated by Franco and Spain you cannot be surprised that they want to protect their heritage now that they can.
You know that their philosophy was settled decades before Franco took over Spain, didn't you? In fact, it was caused due to a dispute started by Real Sociedad.
Besides, you talk like Franco was a dictator only in the Basque country area. Like the rest of the country didn't suffered a bit.
Finally, I think Basques will be way more happy with how they are treated by Spain rather France. Now, and in the past.
Basque nationalism was born in the last decades of the XIX century (like many European nationalisms) with Sabino Arana as the main responsible. If you read his ideas you will find a lot of resembles with the nazi regime. Basque have always been very proud Spanish. Many of the Spanish Empire heroes were actually Basque.
Miguel de Unamuno (a far superior element of the history) that lived in the same period wrote:
We Basques are, because we are Basques, twice Spanish.
We Basques have gone to all the wars in which Spain had to be defended; we went, they did not take us.... we went as Basques and as Spaniards
By the way, if they could form a separate nation they would. They are in the same boat as the Catalans.
No, they would not. Independence hunger is in historic minimum (around ~20%).
In Catalonia, the only elections that were really presented as a "referendum", the "stay" side got more votes. They got less representatives because rural areas (where independent parties are stronger) are overweighted, but they got less votes overall.