Turkey last Wednesday initiated the Euphrates Shield military operation aimed at creating a safe zone from DAESH incursions in northern Syria, from the Euphrates River to Afrin, currently in the hands of the PKK terrorist group's Syrian wing, the People's Protection Units (YPG). Since that day, Turkey-backed Free Syrian Army (FSA) forces have successfully pushed back DAESH while ensuring the PKK's Syrian wing will not become a permanent occupying force in the region. The operation will eventually make inroads of up to 30 kilometers from the border with Turkey, creating a much-needed safe zone under FSA control for civilians in the region.The YPG's response to Turkey's operation, which is supported by the international anti-DAESH coalition, was to attack the Turkish forces deployed across the border, damaging two tanks and killing a soldier. The PKK, meanwhile, continued its spate of attacks, firing rockets at Diyarbakır Airport. It is no secret that the YPG received the majority of its arms from sympathetic western countries, with its media encouraging this dangerous delusion by portraying terrorists, who are accused of human rights abuses on northern Syria's ethnically diverse population, as freedom fighters.What happened over the weekend cannot be dismissed as an aberration or an accident. The YPG, armed by the west, has attacked a member of the international coalition fighting DAESH. The Turkish public is asking what other members of the coalition will do in reaction to this attack.However, the questions do not end there.It is obvious that U.S. Vice President Joe Biden, who supported Operation Euphrates Shield and talked about cutting military aid to then the YPG, during his visit to Turkey last week, obviously has less clout over the terrorist group then he thinks. Is the U.S. losing control of a terrorist group it helped to arm and train?If the YPG attacks all that threaten its terrorist vision without compunction or any regard to international sensitivities, shouldn't it be put down like the rabid beast it is? The U.S. should be open to discuss all options to eliminate this danger to regional stability and be well aware of the fact that Turkey has no tolerance toward a terrorist presence along its borders fed by its allies. Turkey should and will assess the use of the İncirlik Air Base by its allies.It has once become apparent that ignoring Turkey's repeated warnings over a regional nuisance was ignored by its allies until it transformed into real danger to stability. The PKK and YPG, in the past week, have attacked Turkish security forces several times, killing more than a dozen. Temporary measures, such as the suspension of aid or empty condemnations hardly match the gravity of the situation. If a NATO member country that is significantly contributing to the fight against DEASH is attacked with weapons provided by its allies, no measure, however severe, should be dismissed out of hand by Turkey.The YPG's main aim may be to test the tolerance of NATO and its members toward such terrorist acts. A weak response will allow the YPG, with the PKK, to expand its zone of influence or launch a new wave of terrorism across the region. Any failure to stand up to terrorism will transform NATO into a divided, shallow and incompetent international institution, which the world has more than its share, and kick off a new wave of terrorist attacks that the Middle East hardly needs.Turkey has said repeatedly that counterterrorism cannot be left in the hands of subcontracting terrorist groups like the YPG. Both DAESH and the YPG aim at establishing states and have no qualms about engaging in atrocities, including ethnic cleansing, coercion, murder and using chemical weapons, to get what they want. The strategy of supporting one to fight the other will bring nothing but more terrorism to the region.A terrorist is a terrorist. Turkey is against distinguishing between terrorist groups. There can be no selective definition of terror. Those that disregard the security of Turkey and its soldiers should expect nothing but contempt in return. The Turkish public is fully behind the operation launched last week to secure the Syrian border and push back DAESH and is doubly aware of the duplicitous stance taken by regional actors and international powers.