After World War II, and facing a rising threat from the Soviet Union, a group of European and North American countries banded together and signed up to the North Atlantic Treaty.
They believed a collective defence was the best way to ensure future peace.
In the years that followed, the organisation’s membership and goals expanded – there are now 29 countries committed to protecting the security of NATO's members.
But on the alliance's 70th anniversary, some are questioning its effectiveness.
Just weeks after calling NATO 'brain dead' French President Emmanuel Macron met the organisation’s Secretary General Jens Stoltenberg for talks in Paris.
Macron wants his criticism to be a wake-up call for the military alliance.
So what does it mean for NATO’s future?
John Laughland, international law consultant and professor at the University Institute of St. Pius.
Fabrice Pothier, Chief strategy officer at Rasmussen Global and former Director of Policy Planning at NATO.
Yusuf Alabarda, security analyt and retired Turkish Colonel.
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