The recent terrorist attacks in Paris demonstrated once again that in our age terrorism is the greatest threat to the world and humanity.

We have one lesson to draw from the attacks in Paris. Challenging all kinds of terrorist activities is not sufficient. It is urgent to maintain this fight with close cooperation. As Turks, we sympathize with our French friends. Turkey and Turkish people, who have been fighting terror for years, have been subjected to terrorism innumerable times. Lately, we lost dozens of our people in a horrendous twin suicide bombing in Ankara. A Turkish proverb says: "An ember burns where it falls," and the latest ember fell in Paris.

However, all the European capitals are under the threat of terrorism just like Paris and Ankara.

World leaders who gathered at the G20 summit this past weekend in Antalya emphasized the importance of joint action against terror. President Recep Tayyip Erdoğan put specific emphasis on this point during his private meetings with world leaders, including with U.S President Barack Obama and President Vladimir Putin of Russia, and in his speeches addressing the global public: "An effective fight against terrorism has only one way – to jointly fight against all kinds of terrorist activities." So far, many mistakes have been made in this regard.

The majority of DAESH warriors are citizens of countries like the U.K. or France. If the intelligence agencies of EU countries had cooperated with Turkish intelligence on the subject, many French, British or German youth would not have gone to Syria and turned into violent murderers for DAESH.

Likewise, if the EU and EU countries had supported Turkey's offers regarding Syria, DAESH would not have found a chance to come into prominence in Syria and Iraq. If it had fought against Syrian President Bashar Assad as required, he would not have oppressed and murdered the Sunni majority. Then DAESH would not have convinced the Sunni youth by exploiting Assad's tyranny. And parallel to all these, EU countries would not have been confronted with the great refugee crisis they are now experiencing.

Turkey turned out to be right. However, detecting this truth does not matter now. Those claiming that they were fighting against DAESH provided weapons assistance in airdrops to the groups resisting DAESH, and the weapons were finally obtained by DAESH. How smart is this strategy?

How smart is it to provide weapons to the Democratic Union Party (PYD), which is a terrorist organization as dangerous as DAESH, on the pretext of fighting against DAESH? We should have drawn lessons from similar aid in the past that reinforced the Taliban. Supporting the outlawed PKK, the most violent and dangerous terrorist organization in the Middle East, by hiding behind the suggestion that they are fighting against DAESH, is nothing but abetting a kind of terrorism against another.

As intelligence agencies of EU countries already know, DAESH was not the only force behind the recent Ankara attack. It is also known that DAESH and the PKK occasionally engage in cooperation for their own interests and both organizations act as subcontractors for Syrian intelligence agency Mukhabarat. In other words, an effective fight against DAESH is only possible through fighting the PKK, which occasionally battles against DAESH, but can also engage in cooperation with it and organize terrorist attacks for their own interests. To eradicate DAESH, the PKK and the PYD must also be eradicated and Syria must be emancipated from Assad'[s dictatorship and the tyranny of state terror.

It is impossible to resolve the issue of Syrian refugees unless we fight against all kinds of terrorist activities.

One of the reasons for choosing Paris as a target is the fact that DAESH has many warriors who are French citizens. Paris is not unfamiliar to them. Maybe the majority of them know the city very well. The same also goes for some other EU countries including the U.K. and Germany.

PKK members, who are nowadays embraced since they are thought to fight DAESH, and German citizens leaning toward the PKK can also pose a major threat to Germany if we turn out to be right once again and the PKK takes the place of DAESH in the future. Today, the countries that are not returning PKK militants to Turkey are actually undermining their own countries since they are backing terrorists and allowing them to get familiar with their countries. The Paris attacks have also shown this.

Although DAESH is today's threat to humanity, there is no guarantee that the PKK will not take its place in the future.

For this reason, as long as we confine ourselves to fighting against DAESH, we do not have a chance to totally eradicate terrorism since terrorists have no ethical values. They can target you just after cooperating with you.

Both the EU and the members of European Parliament should see this before it is too late. Maybe they will end hosting some PKK militants at European Parliament if they become aware of this.