Former British prime minister, Margaret Thatcher, would never have agreed with her French counterpart, the late President Francois Mitterand, who said “Nationalism is war”. To her nationalism was necessary and good and she felt much as Mitterand’s predecessor, Charles de Gaulle, who said of the French nation,“it comprises a past, a present and a future that are indissoluble.”

But the nationalism that Thatcher fought for was a largely negative force. It antagonized the other members of the European Union. She did not believe her country could learn from them how to carry out economic reform without severe social disruption. She went to war with Argentina without trying to enlist the US as a mediator because it lent towards Argentina’s side.

One can date European nationalism from the Treaty of Westphalia in 1648 which effectively put an end to religious identity being the defining reason for both social cohesion and war. This was the start of the great powers of Europe, the foundation for the US and the Latin American nations, the revolutionary and Napoleonic wars across Europe and the “nation-making” of the nineteenth century which led to the carnage of the First World War.

At war’s end there was the Treaty of Versailles which re-organised Europe according to the principle of “national self-determination” which became a major cause of the Second World War since the European map remained mixed up and illogical. Versailles was unable to create coherent nations, as when it reconstituted a Poland containing a population of two million Germans.

The post Second World War de-colonisation by the European powers created new nations that were as nationalistic as Europe. Post-colonialist nationalism has led to many serious conflicts- as between India and Pakistan, Bangladesh and Pakistan, Rwanda and Congo, Cambodia and Vietnam, Malaysia and Singapore and Israel and the Arab world.

Religion has played a part with India and Pakistan and Israel and the Arab countries but even here nationalism is today the predominant driving force.

David Cannadine writes in his new book, “The Undivided Past” that nationalism only thrives when the people are beholden to “selective myths, the sanitized memories, and the carefully edited narratives that galvanize collective resolve and sustain national solidarities over time.” As the great historian Eric Hobsbawm wrote, getting history wrong is part of being a nation.

We can go further and argue that over time the nation state made war and war made the nation state. This is certainly the lesson of the two world wars. In 1914 millions volunteered to fight out of a shared sense of national loyalty and identity. Yet today one would be hard put to find an historian who would argue that the First World War was necessary or justified. Most but not all – the great historian AJP Taylor is one of the exceptions – argue that, given Hitler’s proclivities, the Second World War was unavoidable. Again millions volunteered for battle. Dying in battle for one’s country was the highest national calling.

The creation of the European Union was conceived as project to ensure that the madness of European war was never repeated again. Europe over the ages has been the site of more wars than any other comparatively sized or populated region in the world. But one of the two most important European nations in both world wars, Britain, today has a powerful minority within the ruling Conservative party who now wish to take Britain out of Europe. Doubtless these parliamentarians if asked would say they are out and out Thatcherites. They seem not to remember the bloody record of nationalism.

Sylvie Goulard and Mario Monti, the current Italian prime minister, in a new book, “To See Further”, write that European nations are modern- and mostly artificial- constructions, in whose name millions have been murdered. If they had not already been created they would not have been created today. They are unsuited to our era. Nationalism is a virus and needs to be contained rather than celebrated- and this goes for the rest of the world too.

They argue that the EU’s members have not been ambitious enough. What is needed to salvage the union from today’s Euro-zone crisis is another institutional redesign, a democratic revolution and a bold leap forward into the future. The genius of the Union is that its 500 million people can focus on the next generation rather than the next election.

Much of their inspiration is drawn from the Federalist Papers written when the union of the USA was in its early stages. Back in the 18th century its authors argued the case for a federal state. Likewise more economic and political union is needed in Europe, not less. The European parliament must become more democratic, independent and able to initiate legislation and raise taxes. The European Central Bank, as does the Federal Reserve in Washington DC, must have more authority and a wider remit.

“Patriotism is the last refuge of a scoundrel”, said Samuel Johnson. Thatcherites exist all over the world. They must be defeated.