The forthcoming British referendum is the single most important event of this decade for the future of Europe.

The Leave campaign has advocated isolationism and retreat from the responsibilities of a major European power. It views Europe as a burden, ignoring history and geopolitics. The Brexiters' approach is potentially harmful for the country and the rest of Europe.

To start with, Brexit is bound to have a significant impact on the country's international standing. It is hardly a coincidence that the United States President Barack Obama, the Canadian Prime Minister Justin Trudeau, and the Australian Foreign Minister Julie Bishop have publicly called for the United Kingdom to remain part of the European Union.

Since these countries largely view the UK as their main gate to European markets, any change in its status would affect them economically. Thus, Brexit could lead to Great Britain's decline in world affairs because the country would lose its value-added position with distant allies.

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Geopolitical effect

To make matters worse, a vote for Leave could trigger a second Scottish referendum if a majority of the Scots opt to remain in Europe. Such a development would certainly damage the image of the UK as a great power.

Moreover, the secession of Scotland could encourage other independent-minded regions, such as Catalonia or Flanders, to pursue similar paths. What good can come out of this disunity? Only uncertainly and political introspection.

Recently, the Remain camp has brought into the debate the geopolitical effect of a Leave vote. In an era of economic globalisation, discussing geopolitics sounds anachronistic and fear-mongering.

But the "Bremainers" are right. For centuries, Europe was a continent plagued by conflict and instability. Tens of millions died from war and mass killings.

Perceptions in international relations do matter. The message that Brexit would send to other Europeans is that the country prefers isolation from engagement.

 

The biggest achievement of the EU is not the single market; it is the establishment of a community of democracies that collaborate in a peaceful environment - so much so that it is unthinkable to imagine French and German soldiers killing each other today.

However, this is not the "End of History" for Europe as Francis Fukuyama once predicted. The wars in ex-Yugoslavia, the annexation of Crimea by Russia, and the conflict in eastern Ukraine have shown that peace cannot be taken for granted in the Old Continent.

Furthermore, the rise of far-right parties in many European countries has brought back bitter memories. Only recently, the presidential candidate of the Austrian right-wing populist Freedom Party called for the "return" of the German-speaking South Tirol - an Italian province - to Austria.

Sending a message

Historically speaking, Great Britain has played a paramount role in European security. It has acted as an offshore balancer whenever a continental power sought to establish hegemony.

In this role the British became involved in the Napoleonic wars and fought against Germany in two world wars. Also, the UK significantly contributed to the containment of Soviet aggression.

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Some claim that NATO membership would help maintain the British presence in the European security architecture. Maybe this is true.

But perceptions in international relations do matter. The message that Brexit would send to other Europeans is that the country prefers isolation from engagement.

For some European countries, such as Portugal, the Netherlands, Greece, the UK has been an old friend who came to their assistance during difficult periods of their history.

A Brexit supporter holds a Union Flag at a Vote Leave rally in London, Britain June 4. [Reuters]

For others, such as Germany, it is a former enemy who behaved with generosity when it was most needed - that is during the Cold War period and the German reunification.

For the French, the Italians and the Poles, the UK is a much-needed ally in their effort to counterbalance German political and economic power.

Put simply, Brexit would constitute a historical anomaly for a country that has sacrificed so much for a peaceful and prosperous Europe.

Another Darkest Hour?

Boris Johnson compared the EU to Hitler. It is useful to remember what happened back then. By July 1940, the German army had occupied France and most of Western Europe.

The dark forces of Nazism had triumphed over freedom and democracy. During what Winston Churchill called the Darkest Hour, namely the period between the fall of France in June 1940 and the Nazi invasion of the Soviet Union in June 1941, Great Britain stood alone against the Axis and faced an unspoken dilemma: to negotiate again with Hitler, or to fight back and help its friends.

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The British people wholeheartedly decided the latter. Thousands of young British men died to liberate occupied Europe.

Later, when the Cold War started, London prevented a communist takeover of Greece and saved the birthplace of democracy from tyranny. This long history of engagement and solidarity cannot go in vain.

The geopolitical destiny of the UK is tied, for better or worse, to the rest of Europe, if only for reasons of proximity.

Therefore, Brexit will not serve the interests of the British people. Far from it. More importantly, Great Britain has a moral obligation not to abandon Europe and its numerous friends and allies.

Despite its structural weaknesses, the EU is the best guarantee for peace and this something that the British voters ought to remember.

Emmanuel Karagiannis is a senior lecturer at King's College London.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.

Source: Al Jazeera