I grew up on an island. It was called West-Berlin and was surrounded by a wall, and a death-strip with landmines and barbed wire, and soldiers with machine guns. For me this was normal.

And then, on a grey November day 30 years ago the unimaginable happened: the wall crumbled. Overnight the world changed. I saw people laughing, crying, dancing in the streets. I saw strangers falling into each other’s arms and holding each other tight. I saw people who had overcome their deepest fear and were truly free. The wall was still standing, but it had lost all of its power. It was magical.

Berlin in November is usually a grey and cold place, but I only remember warmth. My city had become a blissful place filled with life and joy, and an overwhelming feeling of human connection.

It took me many years to fully understand what I had seen that day: that when we overcome our fear and walk together, systems crumble and we create a new reality.

Today, 30 years after the end of the Cold War, there is a new wall that is even more powerful than the Berlin wall ever was. It is an invisible wall that lives in our minds and hearts and under our skin. It shapes our daily lives, our society and our political responses to the world’s most pressing problems. It is the lens through which we see the world and it keeps us from living our best lives.

It is this wall of fear that keeps us from helping the stranger because we see a threat instead of a fellow human being. From sharing what we believe in because others might disagree. From saying ‘No’ when we’ve reached our limit because we might disappoint. And from spending time with our loved ones because we might miss out on work.

It is this wall that makes us hide behind busyness, smart screens, and success when in reality we are drowning in loneliness. It is this wall that numbs our conscience when fellow human beings are being washed onto our shores and are suffocating in container trucks while dreaming of a better life. It is this fear that already imprisons the dreams of our children who are scared of their future and are starting to lose hope.

During the Cold War, when East German politicians told their citizens that the Berlin wall was there to protect them, they themselves knew they were lying. Today, we’ve come to believe our own lie. The truth is that our wall doesn’t protect us. It imprisons us, estranges us from each other, and erodes our humanity.

When we perceive the world around us as a threat, our brains and bodies get stuck in a survival mode that human evolution designed to respond to immediate danger but that is unsuitable for dealing with complex challenges. When our bodies are stuck in fear, our capacity to think deeply, to make sound judgments, and to see the bigger picture is limited.

I believe our children deserve better. I believe we all deserve better. Because in the end, ‘we’re all just walking each other home’. But as long as we feed our wall with bricks of distrust, judgment and doom-thinking, we won’t have freedom nor solve the world’s problems. Because freedom can’t live in fear. And when fear becomes our way of life, we lose our future.

In 1987, it was impossible for me to imagine my city without a wall. Berlin was the frontline of the Cold War and the Berlin wall had become part of my mind and the lens through which I saw the world. Not even in my wildest dreams could I think the two apart.

When U.S. President Reagan visited West-Berlin in June 1987 and said: ‘Mr Gorbachev, tear down this wall!’ he did something remarkable. By using these words, that were inspired by West-Berlin resident Ingeborg Elz, he lifted the fog of fear and made it possible to think the unthinkable. By using these words – against the advice of his entire political team who thought they were naïve, would raise false hopes, and were provocative – he helped us imagine a city without a wall. By using these words, he helped us reimagine the world. Two years later the wall was history.

Today, 30 years later it seems that we have forgotten the power of imagination. It seems we have forgotten that there is freedom from fear. It seems we have forgotten that we belong to each other and that it is up to us to reinvent the world.

What we need now is radical hope and a clear vision of a world without fear. Let us ask: How would a gentler and more loving world look like? And then, let us visualize the answers in such concrete ways that we can see and almost touch the new world. Because everything is born twice, first in our hearts and minds and then, when we embody it, it is born in the world we live in.

This is also why we need a new kind of political leadership that leads from the inside out. Because unless we embody the values we stand for in our daily lives, we are unable to inspire others and bring about true change. If we want change, we have to become the new leaders we want to see in the world.

A new decade of the 21stcentury is upon us. Let us make it the decade of freedom from fear. Let us dare to imagine a more loving world. Let us rise together and tear down this wall. Because we have the power to overcome our fears. And when we do, we change reality. I know it is possible. I’ve seen it happen on the streets of Berlin 30 years ago.