Sentence:  In a sense , the showdown promised by Mr. Hammarskjold 's sudden and tragic death has been avoided ; no precedents have been set as yet ; structurally , the U.N. is still fluid , vulnerable to the pressures that its new and enlarged <WSD>membership</WSD> are bringing to bear upon it . 
Meaning of the word marked with <WSD> tags:  the body of members of an organization or group