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Short answer is Yes.
Not quite so short answer is yes, as long as it does not undermine/contradict the basic tenets of the NATO charter.
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Turkey does not like Russia - do not forget that Turkey joined NATO (and has remained a member) largely because of the fear of Russian aggression in the Black Sea in general, and re the Bosphorus in particular. They are trying to sit on the fence a bit for political purposes (justified or otherwise) and due to their main supplier for oil and natural gas being Russia.
Also, for those who might not be aware, Turkey effectively has the 2nd or 3rd most powerful military of the European NATO members. They could clean the Russians out of the Black Sea and Crimea pretty much by themselves - if they wanted/had to. Short of using nukes there is little Russia could do to stop Turkey in their area of responsibility - although they could be seriously hurt if the Russian forces were allowed to concentrate on the Crimea/Black Sea front.
Obviously there is no guarantee, but I do not think there is much reason to worry about Turkey's allegiance.
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List of active Turkish Air Force aircraft - Wikipedia"
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Turkish Naval Forces - Wikipedia"
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List of equipment of the Turkish Land Forces - Wikipedia"
PS: Also, Turkey is 'steadily' becoming a country of 'haves', ie their economy is growing and they are merging more and more with the world of higher standards of living. They do not wish to lose that.
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Economy of Turkey - Wikipedia."