We had two world wars, as well as several other extremely violent conflicts. The 20th century is drawing to an end with the triumph of liberal democratic ideology. The role of nation-states has changed, as you pointed out in the article, and globalization has become a phenomenon in the late 20th century. I do not have a good answer to that. Because of this, we have almost unchecked movements of people, goods, ideas, technology, drugs and money.
Finances are vitally important within international borders.
National governments find it very difficult to control these flows. I believe people are seeking their identity and reassurance in smaller and smaller groups, producing the trends toward the emergence of ethnic communities and regional communities, and so forth. We see this going on in Europe, where on one hand the European community continues to develop, while at the same time there is a trend toward the development of much narrower identities. I would be very surprised, for instance, if the United Kingdom exists in its current form in 20 years. Movement toward the independence of Scotland is well under way, and I think, very probably, Scotland will in due course become independent.