A public show of emotion is rare in Brussels, the political capital of the European Union. Yet things were very different this week, as the departure of the United Kingdom from the historic club became all too real.

I have reported on Brexit often since the June 2016 referendum, analyzing the highs and lows of the ensuing debate and negotiations. I generally consider myself to be hard-boiled when it comes to politics. But when the colors of the Union Jack were projected onto the facade of the Grand Palace in the heart of Brussels and a number of Brits waved EU flags for the last time, I must admit it gave me goosebumps. After 47 years, the departure of a country so pragmatic and successful was greeted with a sense of melancholy bordering on sorrow in Brussels.

I have reported for Brussels for years, but on Wednesday, I saw something I had never before witnessed:  European parliamentarians sang "Auld Lang Syne," with many crying as they did so. That was an expression of the fact that Europeans not only have a rational connection to the UK and its citizens — a country that has shaped the EU in so many ways — but also a very emotional one.

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Once again, with feeling

Fondness for those in the island kingdom will remain, yet so will my own personal inability to understand Brexit. Even after scores of discussions with Brexit supporters, I have never grasped what exactly the real-world advantages of isolation are supposed to be.

For many in the UK, especially the erratic, populist Prime Minister Boris Johnson, it is not about economic or political opportunity, but rather about a feeling — a feeling of independence, of controlling one's own destiny.

It is the feeling that one should be an empire that rules the waves, and not part of a collaboratively organized European community. While attending a UK Conservative Party conference, one delegate I spoke with told me the UK wanted out of the EU "because we are British." That self-confidence, that strange attitude, seems to me to lie at the heart of Brexit and the UK's yearslong internal conflict over the EU and Europe itself.

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Brexit isn't the end

Cogent arguments pointing out that the UK has not been patronized since joining the EU in 1973, but rather treated as an equal partner — at times one that was afforded advantages over other members — prove useless in the face of such attitudes. For some politicians, Brexit is a type of religion, one with the built-in promise of salvation. But will things really be better when the UK is finally free of Brussels?

Populism has won the day. It has been as victorious in the UK as it has been in the US. It is no coincidence that the US president and the British prime minister, both of whom share similarly obscure political visions, are best buddies.

For me personally, the melancholy brought on by the UK's senseless departure is mixed with a certain optimism that reason will eventually return. In the event that the UK and Northern Ireland once again fall on hard financial times, as in 1973, most will likely think of the community of nations on the continent. When Britons see the UK's political influence wane after Brexit it is possible that London will once again long for that community. A return to the EU in 10 years' time is not impossible to imagine.

In my view, our British friends are chasing false promises and needlessly embarking on a perilous adventure — and that sends chills down my spine. Brexit, is, after all, a feeling.