There are two kinds of nationalisms (even if cataloguing like this is Platonism and reducing the complexity of the world, thus losing information... IE, this is not true, but a pedagogic lie).
First you have the normal one. Based on culture and ethnicity. All over the place. Might not be bad, as long as it doesn't turn aggresive.
Then we have the other one, based on ideology and values. We have it in the USA, France and the old Soviet Union.
These are often more dangerous as the nations feel they have a creed or ideology to spread, a mission civilicatrice.
But as I said above, nothing is as clear cut as this. Soviet nationalism was also based on Russian imperialism, the American variety have strong WASP elements and French republicanism of course also have ethnic markers. But it's still very different from the view in Germany or Sweden (even if the Swedish elites are much closer to the French view). Peak oil is not an energy crisis. It is a liquid fuel crisis.
Civic nationalism though... That can still be used as a cover for armed robbery on a geopolitical scale, to spread "democracy" or promote "womens rights" and so on. Peak oil is not an energy crisis. It is a liquid fuel crisis.
