The Basque Country pioneered the industrial revolution in Spain and still is one of the richest regions in Spain. Bilbao suffered a lot in the 1980's when it lost its heavy industry, but it has turned itself around (much like, I understand, Glasgow has).
The Stormont Agreement and the Scottish Assembly are a joke compared with the level of self-government the Basque Country enjoys. The Basque Nationalist Party has ruled continuously since 1979. The Basque government has a regional police force, raises all taxes, controls health, education and infrastructure and has two TV channels. Education is available in Basque.
Whatever wrongs by Franco motivated ETA in the 1960's have been righted by now. That is why they are dead enders. The only things the Basque Country doesn't have are 1) Navarra and the French Basque Country; 2) a foreign policy; 3) free and fair elections; 4) ethnic cleansing of those not sufficiently Basque.
On the issue of free and fair elections: non-nationalists are afraid and have been for years thanks to intimidation by ETA and its sympathisers; Spain has a law of political parties that uses guilt by association to keep ETA sympathisers from taking part in the political process.
On the issue of ethnic cleansing: Basque Nationalism is originally (Sabino Arana) a racist reaction against migrant labour from the rest of Spain since the 19th century. There is also a separate strand of right-wing "Spanish" traditionalism (God, Fatherland and King) that has cost Spain 4 civil wars (the Carlist wars, and the Carlists's role in the Spanish Civil War on Franco's side). Can the last politician to go out the revolving door please turn the lights off?