Turning right, she would have come face to face with a giant stack of metal sea-container units standing two storeys high. The ultra-VIP would have been invited to nod approvingly at a life-sized Ford Ka tipped on its nose inside a gallery (wittily named "Cargoes"), proudly bearing the names of its sponsors, Maersk, James Fisher & Sons, WNI Ocean Routes and P&O. The rationale behind this glorified marketing opportunity is that since car manufacture today is an international business, involving the transport of car components from one part of the globe to another on the high seas, cars actually tell the story of the sea. Which is about as logical as the Fleet Air Arm Museum at Yeovilton exhibiting air-freighted bananas in order to tell the history of flight.
For all the brave new architecture, the ingenious engineering, the superlative execution, the museum's new display regime merely underlines the intellectual panic at the heart of some of our greatest cultural institutions. Access, access, access is the mantra buzzing around the museum directors' heads, and it seems that in their desire to grip the imagination of the public, they have made some fundamental mistakes. Despite the fact that the architectural remodelling provides 30 per cent more exhibition space, a smaller number of items from the museum's superlative painting collection will be on show than before the JCBs moved in.
The "Art and the Sea" gallery on level 2 - a cramped, low-ceilinged room with pictures hung too closely together and poorly lit - compares with the tall, elegant Special Exhibitions gallery currently housing a photographic display. World-famous images, such as Hodges's visceral portrait of the explorer Captain James Cook - "William Hodges patch'd his colours so thick that it almost makes you want to be sick", as some 18th-century wit said - Peter Lely's complete series of English flag officers, and Canaletto's painting of Greenwich itself are nowhere to be seen.
Ah but, the directors say, you can access (that word again) some of the picture collection via the IT archive (called "Search Station"), which allows you to scan the images in a myriad different ways. But what is the point of having a museum building at all if you claim that providing a virtual equivalent is better?
This nervous antipathy towards the museum object is shared by Dr Alan Borg, currently director of the Victoria & Albert Museum, who stated in a recent BBC2 Close-Up programme about the ambitious Spiral project that "the traditional concept of a museum with long galleries full of glass cabinets filled with objects one after the other is simply going to be unsustainable for the future".
An extraordinary statement - career suicide, even - for a person to make when he is charged with the care of one of the world's great treasure houses. "Unsustainable": the word is simply terrifying. But then connoisseurship - the special appreciation of objects and works of art - has just become another c-word.
Compare this with the sentiment expressed by the director of the Wallace Collection, Dr Rosalind Savill, in a talk she gave last year: "I love objects. Yet when objects enter a museum the current view is, in theory, apparently, that we curators should be embarrassed by them, almost having to apologise for pickling trinkets from the past. But the practical reality is rather different. We are the caretakers of some of mankind's greatest achievements; these objects can arouse our curiosity, inventiveness and imagination, whether we are five years old or 95, and increasing visitor numbers show this still to be so."
While the wisdom (or folly) of such statements merely deepens the debate in the art world about the future purpose of museums, the issue of what has happened in Greenwich presents a more significant, if rather subtle, warning to us all. In shifting gear from being a museum about maritime history to become a theme-park showcase for government-backed environmental projects and commercial achievement, the museum re-defines our national image: "national", "maritime" and "museum" are words loaded with special frisson. To quote from one of the exhibition labels lurking in the "Art and the Sea" gallery: "Nations have frontiers that are defended or extended. Images of the coastline or of the fleet flying the flag abroad have a particular significance when the sea is a nation's natural frontier."
"Ultimately," it continues, "the image of the sea has been the image of the nation". Has been. The past tense is doubly revealing: firstly, because the truth of the matter is that we are no longer a naval power of world importance (very little is made of the Falklands War - our last significant armada). Secondly, our fishing fleets are decimated. Also, the history of dead white males winning sea battles against pesky foreigners (now our European partners) is not something to which our present government expresses any attachment.Strange, when you consider that our Prime Minister seems to like to be portrayed as a hawk.
Nelson has survived. There's a gallery devoted to his funny old life safely tucked away on level 3 at the Museum of Sea Trade and Ecological Sustainability (oops! I mean the National Maritime Museum). Not far away, a Madame Tussauds-style dummy of a Maori dressed in rugby gear straddles the floor. Downstairs, children try out the various themed caves which look smart now, but which some curators privately acknowledge will require constant costly maintenance after six months or so of buffeting. In being encouraged to cater for children - a laudable aim - too many museums hysterically abandon their adult visitors to their own fate in knee-high exhibition landscapes.
"Traditionalists may be uncomfortable," wrote Roger Knight, the museum's deputy director, in last month's issue of History Today. "Where are the reassuring, massed notions of British supremacy, when the biggest and best ships carried naval power, trade and traditions to those parts of the world where the sun never set?" he asks, knowing full well they have been tidied away in accordance with a political climate in which Foreign Office policy dictates that only new, fashion-conscious images of Britain are presented to the world. "Those values were never a reality for a large part of the population, and will never be accepted by the citizens of the next century."
After the death of ideology (national, spiritual, political) comes the revision of history; so we should have expected this. Stephen Deuchar, responsible for the museum's redevelopment - including building works and display - is now director of the Tate Gallery of British Art. Look out for the Daewoos in the Duveen Galleries.
National Maritime Museum, SE10 (0181 858 4422), open daily, 10-5. Museums Week (today to 23 May; info 01795 414 731) allows free entrance to nearly 100 museums nationwide.