Hooray. Aucklanders finally have Queens Wharf. But is the best use for it really a new terminal for an industry that could be in terminal decline?

It was this very cool graphic in the Atlantic – still my favourite magazine – that got me wondering.

Aucklanders got some great news yesterday – we're finally to get our hands on Queen's Wharf, the finger of concrete and steel that reaches out into the Waitemata at the bottom of the city. The Ports of Auckland has finally honoured their word and released the wharf into public ownership. Come to think of it, if the wharfs were fingers, Princes Wharf would be the index finger and Queen's Wharf the middle finger. So read into that what you like, Ports of Auckland.

However now that we've got the wharf, what are we to do with it? John Key wants to make it "party central" during the Rugby World Cup. Apart from the lame name, I've got no problems with that. It'll be a great public space, with people able to travel in by train and bus from all over the city and the bars and restaurants of Britomart and the Viaduct keeping the punters satisfied.

But that only accounts for a couple of months of use. It's long-term plan is less certain, and there needs to be some serious discussion about that, rather than the local politicians simply pushing their new favourite barrow – cruise ships.

Mike Lee and John Banks, men who don't agree about much, are of one mind about the need to build a cruise ship terminal on the wharf. According to the cruise industry's PR folk, each ship is worth about $1.6m in tourist spending. Lee and Banks – the Isaac and Gopher of Auckland politics, for you Love Boat fans – are likely to get support from number one Auckland-watcher Brian Rudman (Doc?), because he believes his dream of a waterfront theatre for the Auckland Theatre Company fits hand-in-glove with the building of a new terminal. The both need large lobbies, an attractive forecourt etc.

But let me take you back to the Atlantic for a moment. The June issue dedicates a double-page spread to the Oasis of the Seas, the new cruise vessel due to be unveiled in November, which will be the longest, tallest, heaviest, and widest passenger ship ever built. It's stunning. But writer Rory Nugent points out that the ship was ordered in 2006, "near the height of the [cruising] boom". Royal Caribbean – the world's second largest cruise company and the business that will own the ship – is carrying $9.3 billion in debt and have a sell recommendation attached to its shares by Goldman Sachs, which has "little enthusiasm for the cruise industry as a whole".

The recession has sliced into the profits of cruise companies, which have been offering huge discounts to ensure their boats leave the docks full. (After all, what's more depressing than a half-empty cruise ship? It's like a clown with no make-up.) In January, Royal Caribbean reported a fourth quarter profit of $US1.5m, down from $70m in the same quarter a year earlier.

All over the world, sub-editors are pulling out the maritime puns to describe the industry – cruise ships are sailing through rough waters, or the bottom is falling out of the business. Cruise company CEOs are saying it's just a temporary dip; and they'd better hope they're right. According to Cruise Industry News a whopping 38 new ships are due to launch worldwide by 2012.

Those order were based on a history of solid growth in the industry dating back to the 1980s. Now revenue's down and the cost of capital to pay for these giant new ships will be steep. Rough waters indeed. Perhaps the industry will bounce back and we'll be well placed to profit. But we should be careful. Auckland politicians have a history of horribly short-sighted decisions when it comes to building for our future, as Lee himself has written about. The decision by the Auckland City Council in the 1950s to back cars over trams was one of the worst political decisions in New Zealand's history.

So let's not make the same mistake with ships. Does Auckland really want to bet its waterfront on this industry?

When we finally get control of a precious but small piece of our waterfront, do we really want to take this kind of commercial risk with it? Can't we dream bigger than making room for another 30-odd cruise ships and welcoming another few thousand rich, elderly Americans?

Lee, who just last year was hailing Queen's Wharf as "a potential jewel in the waterfront crown", is now saying we don't need a gold-plated development down there. But I'm with John Key, who has urged the city leaders to use Queen's Wharf to make Auckland's waterfront world class. This opportunity is too rare to miss.

My dream remains a signature piece of architecture that captures the spirit of our nation, as I wrote about here last month.