LONDON - Every summit attended by a United States president requires the toil of hundreds of American officials, from those who prepare the intelligence briefs or the traditional "what you should say if he asks you this" questionnaires to the communications and security details.

But the forthcoming summit between President Donald Trump and North Korean leader Kim Jong Un is an exception, for although those hundreds of officials have been put to work, seldom has an American leader put so much of his own personal stamp on such a historic gathering.