OPINION: The world is building fences. Here's why we should worry

In December 2015, the BBC wrote: " EU border security becomes new mantra". Not only Europe but larger parts of the world are going through a phase of increasing disintegration: the Brexit referendum, discussions about the exclusion of Greece from the eurozone and the beginning of the construction of fences along the green borders of barrier-free Schengen.

Near Schengen, on 14 June 1985, the picturesque town in Luxembourg, five European countries signed the agreement which led to the creation of Europe's borderless Schengen area. In light of mass flows of migrants seeking asylum in Europe, Hungary blocked migrants from onward travel to the rest of Europe and constructed a four-metre-tall fence along sections of the border with Serbia - a country not part of the Schengen area.

THE HIDDEN COST OF DISINTEGRATION

What would be the impact of re-establishing barriers? Citizens would face long-forgotten burdens: the northern Europeans, for example, would experience long traffic jams at the Brenner Pass on the way to the holiday destinations in the south. Labour markets would also be affected: 1.7 million people cross European borders every day to get to work. Consumer prices would rise due to the forced slowdown and necessary adjustments along the supply chain. Waiting and inspection times at the borders would need to be factored into the prices of goods, as well as the changes required to the highly cost-optimized just-in-time concepts - largely applied in global manufacturing in the automotive industry - and the efficient goods supply out of the distribution centres. Many of the products made available by bilateral and multilateral agreements would disappear from supermarket shelves.

Disintegration would affect the competitive position too. Europe, for example, might find itself in a very disadvantaged situation given that Asia is continuing to integrate. What if TTP arrives and Schengen leaves? There might also be explosive geopolitical risk involved, with Crimea, Ukraine and new Chinese islands in the South China Sea heating up the debate. As new fences go up across Europe, what tensions could result from countries such as Spain, Italy and Greece being left more or less alone with new waves of migrants?

TIGHTENING UP SECURITY

The world has experienced decades of advancing global integration. Increasingly open borders and many trade and investment partnerships have strongly contributed to the prosperity and wealth of people and nations. International organisations and agencies have not only supported global growth but also established institutions in charge of dealing with the risks of reducing national barriers. Organisations have developed international ties and many platforms of collaboration to fight crime and terror have emerged.

Interpol - the International Criminal Police Organization - has strong links with Europol, the organisation coordinating the local police forces across Europe. Within countries, ministries and agencies are increasingly working together. Germany, for example, has established the GTAZ - the Joint Counter-Terrorism Centre - an autonomous authority and co-operation platform used by 40 internal security agencies.

The private sector has launched initiatives to protect staff and assets against terrorism and other threats across the globe. Since the attacks of 9/11, security measures have been tightened. Today, individuals and companies are checked against the sanction lists of the US and Europe. Employees appearing on the lists are no longer allowed to be paid a salary, and companies are excluded from doing business. Though, as the Panama papers show, we have not yet closed all the back doors.

BATTLE ON THE INTERNET

Social media helps terrorists organise itself and recruit new fighters. On the other hand, the FBI uses internet surveillance software like Carnivore to identify and stop attacks. Organisations such as the Search for International Terrorist Entities are scanning propaganda material and training manuals, and sharing the insights with other organisations. Technology trumps. The internet has the potential to flatten borders while reducing risks. The more people are active on the net, the better economic value can be extracted and (potential) terrorist activities monitored. Which also does not come without concerns and complexities - as the discussion between Apple and the FBI shows.

Governments have the obligation to protect citizens and the right to control borders. However, what are the effects of the potential disintegration on citizens, migrants and the economy? The Bertelsmann Foundation warns that re-establishing permanent border controls in Europe could produce losses of up to €1.4 trillion over 10 years.

We need to understand and be mindful of the impact of our decisions on the economy. All the same, should we apply economic reasoning to a decision on whether or not to offer a helping hand to people in severe need?

Wolfgang Lehmacher is head of supply chain and transport industries, World Economic Forum.