Human history is littered with bridges and walls, physical and ideological. Through the centuries, the pendulum has swung between preferences for either walls or bridges, dictated by ideology, religion, politics, fear, intolerance, exclusivity, isolationism and imperialism.
Migration, driven by need and greed, has been another factor impacting on borders and changing the face of the world: in many instances migrants from Europe today control previously native lands in the Americas and other parts of the world, outnumbering the native inhabitants.
Depending on how you define progress, these migrations did lead to progress in many areas. However, the impact on indigenous traditions, structures, ways of living and the environment were huge and devastating. Self-serving colonialism, contributing to migration, also left deep scars in the social fibre of former colonies.
The new world order, introduced after the Second World War, accelerated the process of globalisation, making the world a smaller place, a global village. Walls, ideological and physical, were being replaced by bridges.
The EU has been a prime example of this trend. However, a global economic slump and recent mass migration created a wave of populism across Europe and swung the pendulum away from bridges to walls again.
Blatantly riding this wave, a US president came to power on the support of a minority of US citizens vulnerable to his populist slogans. The world is still in shock and the right wing in Europe is jubilant about its perceived ally in the White House.
This will be a watershed year that may decide whether the world will retreat into isolationism and exclusive nation states.
My view is that the world has progressed too far on the road to globalisation to now return to a world order that existed before the Second World War. A vital factor will be whether the eroding middle ground will be strong enough to withstand the wave of populism.