NATO (North Atlantic Treaty Organization) is an invitation-only membership alliance that includes 30 nations, big and small. It expanded after the fall of the Soviet Union to include many former Soviet states, including Estonia. But not Ukraine.
The NATO mutual defense provision is Article 5: an attack on one is an attack on all. However, Article 5 is often not fully understood. To reach its mutual defense mechanism, which is not automatic, all member nations must agree to invoke it, and then each member nation may decide how much, if at all, they want to be involved.
There is one way of looking at NATO as a solemn solid inviolable bargain. But the conditions attached to Article 5 indicate that it is a little porous and open. Not to disrespect a valuable tool of global freedom, but a little bit of “only if you feel that you can or should.”
All of which brings us to the distinction between letter and spirit. The letter of NATO is pretty clear. If you are in it you get the benefits and responsibilities (such as “tell us if you are willing to fight or not”). The spirit, of course is much bigger. NATO was established in the wake of World War II, to assure a stance of “never again” will we stand down, always again will we stand up, when lives and freedom are threatened.
With absolutely no disrespect to Estonia, it has made a very favorable deal. If even one Russian soldier crossed its border and committed one act of war, Article 5 would be considered (maybe invoked, see above), and the integrity of its territory and the lives of its 1.3 citizens would be protected by the most powerful armies in the world.
For three weeks, the integrity of Ukraine and the freedom of its 42 million people has been under attack, attacks that will not soon end. Yet expert statecraft and realpolitik have been dictating that NATO need not be directly involved, should not be directly involved.
In 1937 Jean Renoir made the film Grand Illusion (La Grande Illusion), on all best of all time lists, including best anti-war movie. World War I was a fresh memory, the foundation of World War II was being laid. These borders, these nationalities, are all grand illusions that we embrace but only lead us farther away from the primacy of our humanity.
It may be that one small free nation deserves the full force of military might, while another much, much bigger nation, because it sits on the other side of the NATO border, deserves all the non-military help we can muster, including our spiritual support, but is going to be left to fend for itself. That is a grand, and ultimately tragic, illusion.