We can no longer apply the classic criteria to clearly determine whether and when we should use military force. We are waging war in Afghanistan, for example, but it's an asymmetrical war where the enemies are criminals instead of soldiers.

On the other hand, all kinds of adventurous schemes to add security checkpoints to subway and bus systems have been circulating since the London attacks. This is nonsense. No one can guaranty 100 percent security.

Procedures outside the stadiums and in the parking areas still need to be optimized, for example so that emergency medical services can leave the grounds on their way to the hospital faster.

And now when we hear that Iran and Iraq plan to cooperate more closely and that a fundamentalist is coming to power in Tehran - a man about whom we cannot be sure that he is absolutely averse to terrorism - it is very worrisome.

There is no question that Iraq is one of the main problems. You'd have to be blind not to see what a magnet and generating force it's become for terrorist groups.

The hatred Muslim extremists feel against the West feeds on certain conflicts in the world.

The attacks on the Paris Metro in the 1990s were committed by members of the local Muslim community, immigrants from the Maghreb region of North Africa.

This fanaticism is what feeds terrorism. And this is precisely why Muslims must play an active role in opposing hate sermons and incitement to terrorism and extremism in their mosques.

Who knows what would have become of me, if my parents had not had their influence on me.

We cannot allow violence from militant activists to dictate where and how democratically elected state leaders hold their meetings.

We feel very honored to have been offered the responsibility to host this great event, Berlin is a wonderful city that is developing at a tremendous rate, and this decision means that we can now prepare to welcome the world's best athletes to a fascinating place.

The vast majority of Muslims living here are peaceful citizens. Unfortunately, however, we also see religious and political fanaticism among Muslim groups in Germany.

The terrorists who committed the 2003 Istanbul attacks were locals, that is, Turks. And when filmmaker Theo van Gogh was murdered in the Netherlands last year, the murderer and his supporters were also part of the Muslim community.