The Miracles of Realism
By ROGER COHEN
Vietnam teaches several lessons, the first of which is that the United 
States can have normal relations with countries whose political systems 
and ideologies it rejects.

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I'm not interested in this NY Times article, only in the grammar of its 
openeing sentence: " ... countries whose political systems and 
ideologies it rejects"

" ... countries whose ... " ?  Interesting.  I thought 'who' (whom, 
whose) was reserved for reference to nouns that denote people or other 
animate objects.