"Islam must be enlightened!," my PE teacher declared, waving his index finger in my face. It was noisy in the gym. While the other pupils in my class continued with their exercises, he had isolated me from the group for no good reason, in order to deliver a monologue about Islam in Europe.

He was not really known for in-depth theological discussions; he did, however, make no secret of being a staunch Christian. "Only through Enlightenment, as was the case with us Christians, can Muslims be integrated into our German society," he continued. I tried to explain that things were more complicated than his comparison suggested but I couldn't get a word in. So I just nodded.

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Today, I have little in common with that 15-year-old girl. The debate, however, about the alleged absence of Enlightenment in Islam has not changed since my youth. Head scarves, parallel societies, swimming lessons, minarets, circumcision – the same issues come up time and again.

We are obviously running around in circles since politicians haven't come up with a solution to the "Islam issue" to this day. In the event of a ferocious Islamist act of terror, the urgency of a discussion is pointed out immediately. That discussion, however, primarily leads to fingerpointing at Muslims. It goes on for a short while, before the issue dies down, only to resurface and start all over again.

Listen – don't patronize

Yet, in discussions about the danger of Islamism and Islam in Germany Muslims hardly get a chance to speak. People speak about them, but rarely with them – like my former PE teacher, who showed no interest at all in my opinion and whose statement implicitly suggested that I was not integrated into German society.

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In a similar way, Germany's mainstream society patronizes Muslims to this day – by calling on them to practice a liberal Islam which is compatible with "German values," usually implying that this can only be achieved if the Islamic faith is not practiced in a visible manner.

It seems to be of secondary importance that the majority of the Muslim community in Germany are liberals and reject all violence. Islamic scholars as well as a number of Islamic associations and organizations have been trying for years to initiate a constructive debate about Islamism.

But instead of listening to them, German politicians resort to platitudes and trivialities or curry favor with right-wing political parties. Therefore it's hardly surprising that terms such as "political Islam," "fundamentalism" and "jihadism" are wrongly used interchangeably.

Don't give way to Islamists

Moreover, most victims of Islamist attacks worldwide are Muslims. The fight against Islamism is therefore a common struggle by Muslims and non-Muslims. That's why it is crucial that both sides talk to each other and approach one another.

If, out of frustration, the vast majority of liberal Muslims no longer raise their voices, who will take over? It is the very division of the center of society which Islamists draw their strength from and which pushes young people into their hands. This is, admittedly, a simplified analysis – in fact, there are several different reasons why Islamism still has a strong appeal in Europe and radicalizes primarily young men.

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The mere fact, however, that someone is wearing a headscarf or sporting a beard, does not want to take part in swimming lessons or has been circumcised, is definitely not one of those reasons.

Blanket suspicion means rejection

If mainstream society suspects Muslims to be radicals simply because they practice their faith, it rejects them, simultaneously casting doubt on their right to freely practice their religion in Europe. Is stigmatizing Muslims in accordance with our basic values?

And how can it be explained logically that European governments officially declare war on Islamists but simultaneously supply arms to Islamist regimes and engage in trade with them? Where have the principles of European Enlightenment and reason gone all of a sudden?

If we really want to confront Islamism, we have to meet Muslims on an equal footing instead of just wagging our index fingers in front of their faces — that finger being, ironically, an Islamic symbol of god's unity. And furthermore — those who permanently point their index finger at others, obviously point the three remaining fingers at themselves.