Britain's Prince William thinks people worry over "rapid techonological and social change."
Prince William
The 33-year-old future king made the statement in a biography of the Queen - written by Lord to commemorate his grandmother's longest-serving reign - and said it is "challenging our communities".
In the book's foreword, he wrote: "Over the last 90 years, the world has changed more rapidly than at any time in history.
"When my grandmother the Queen was born in 1926, the wounds of the Great War were still healing, but few would imagine how soon they would be reopened.
"The confidence of the previous century had morphed into uncertainty and many worried - as they still do - about the challenge presented to our communities by rapid technological and social change."
Fellow Royal biographer Hugo Vickers believes William's comments indicate he will rule "the way he wants to" when he is king.
Hugu told Daily MailOnline: "I think Prince William and the younger Royals learn by example which is one of the great advantages of an hereditary monarchy.
"He will do things the way he wants to do them in the fullness of time of course, but he will no doubt bear in mind how she does things."
In the foreword, the Duke of Cambridge paid tribute to Elizabeth, 89, and described her "perspective and love of family" as well as his 94-year-old grandfather Prince Philip's continued "support" of his wife throughout her reign.
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