On June 11, NATO ambassadors gathered in an emergency meeting at Turkey’s request to discuss the rapid expansion of radical Sunni Islamist militants in northern Iraq in which they took control of Mosul and Tikrit. That same day, the Islamic State of Iraq and al-Sham (ISIS), an al-Qaeda spin-off group fighting in both Iraq and Syria, seized Turkey’s Mosul consulate, taking the consul general and his 48 staff members hostage. Earlier in the week, ISIS also took 31 Turkish truck drivers hostage.

“Ambassador Fatih Ceylan outlined Turkey’s perspective of what is going on in particular in northern Iraq and concerns over the safety of the diplomats and children,” David Lute, US ambassador to NATO, told Al-Monitor June 12 in Ankara at a German Marshall Fund event on the upcoming NATO summit. “We did not gather under Article 4 or Article 5.”

According to NATO’s founding treaty, any member state can convene a meeting of member countries under Article 4 to “consult” with them when it feels its independence or security is threatened. This sends a strong political message to the greater world that a NATO member country is concerned about a particular situation. Turkey invoked Article 4 twice in 2012 over the Syria conflict, and the alliance approved the deployment of Patriot anti-missile batteries along the border with Syria.

Article 5 is known as the “one-for-all and all-for-one” article, which has only been invoked once since the establishment of the alliance more than six decades ago, when the United States came under al-Qaeda attack in September 2001. NATO supported the US action in Afghanistan, but stopped short of extending the same unity in its decision to invade Iraq. NATO, however, provided training to Iraqi forces, which ended in 2012.