The attempted coup at the US Capitol is a warning: the future of global democracy is in danger

• The attempted coup in Washington is a warning sign of historical dimensions.
• By inciting his followers to carry out such acts, Trump has confirmed the worst fears of his sharpest critics.
• Three particularly negative consequences could result: the US could be weakened on the world stage, empower a political counter-reaction, and embolden tech companies to become more active censors.
• Mathias Döpfner is CEO of Axel Springer SE, the parent company of Insider Inc.
• This is an opinion column. The thoughts expressed are those of the author.

It is a dark day for the United States and its allies. It was previously unimaginable, even for the skeptics, that the president of the world's biggest democracy and the leading Western power could personally call for a coup against democratic institutions, that people would actually attempt to carry out that coup, and that the storming of the Capitol would lead to gunfire and fatalities.

This event is a warning sign of historical dimensions. And there are three particularly negative consequences we might face.

These events could weaken the US and make things easier for its critics all over the world

When a President - because he is unwilling to accept his defeat - can so easily incite citizens to besiege such a symbol of parliamentary democracy and of a free and open society, that is a sign of weakness. It shows how damaged and ailing American democracy has become.

The exposure of America's weakness as an extremely polarized society is an open invitation to its totalitarian opponents - both inside its borders and abroad - to try more of the same. America's standing on the moral high ground has become even more fragile overnight.

In the future, when a democratic politician expresses criticism of a non-democratic counterpart, they will no doubt have to put up with a scornful rebuke. Any banana republic could simply retort - put your own house in order first!

Trump has emboldened an extreme counter-reaction

By refusing to accept the election results, by speaking of fraud and by dangerously inciting his followers to violence, Trump is merely confirming what his sharpest and most fundamental critics have said about him all along. Removed from reality by his narcissism, he is unable to come to terms with his defeat, and thus also unable to cope with his democratic rivals.

At the end of his period in office, it is Trump himself who has delivered the proof that he is exactly what his far-left opponents have always said he is: a danger to democracy. Anyone who tries to play this down using finely articulated arguments merely strengthens the left, which is already very strong at all levels of the incoming government. The US will shift to the left. Possibly very far to the left. And that would not be good for America or for the rest of the world.

The rise of social media as censors

Twitter and Facebook have become active censors, blocking the president's posts. The decision was absolutely justified in this case and driven by good intentions. But a taboo has been broken, and that could have consequences.

The social media platforms have long taken on a role that is very different from a mere technological network. They have become part of the journalistic-political system. And these companies are increasingly reminiscent of Hans Magnus Enzensberger's dreaded "Consciousness Industry." If the ban on Trump's accounts remains an exception, then it is acceptable. But if censorship were to become a habit among such global monopolies in less clear-cut cases then the open society of the West would no longer be open.

We can, at least, draw optimism from the resilient nature of America's institutions. Security and the democratic order were quickly reinstated. And both the House and Senate continued its session after the rioting was over.

If the US and its allies are to reach the right conclusions from these terrible events, then democracy will emerge from this stronger than before.

But if the enemies of democracy - Moscow, Tehran, Beijing - are able to successfully assert themselves as the better alternative because values like freedom, human rights and the rule of law are only half-heartedly defended, if socialist phantoms of the past are able to win over people's hearts because capitalism appears to be nothing more than a system for increasing the wealth of an ever-smaller privileged circle, and if the capricious whims of excessively powerful tech platforms become even stronger because politicians no longer understand the digital world then Wednesday's actions by Trump and his disciples will have symbolically heralded in the beginning of the end for democracy as a successful global model.