Comment: But the other articles demand specific performance.  If a country does not honor its obligations, it has de facto withdrawn from the organization.

P.S. Wake up call.  This whole topic is nonsense.  The US can never send troops against Russia.  When the US kills the first Russian, they will launch the first nuclear missile aimed at an American city.  This is the real deal.  We have gotten used to being the cat to the other country's mice.  But Russia is a big dog.  Thinking gets skewed.  For Hillary to claim she would defend the former Soviet states in the Baltic region means she will endure nuclear holocaust.  Russia will not blink because they know that no sane American president would invite a massive Russian nuclear attack which would wipe out the USA if we sent even one nuke in retaliation.