Apart from a deepening political and social divide, there is an increasingly shrill debate over the relative strengths of the US and European economies.

Much of the terrain of this argument is fought over by geeks who worry far too much about the proper measurement of productivity.

In the euro area's corner, we have those who argue that the key economic difference between the two regions is the number of hours worked. Apparent productivity differences between Europe and the US melt away when we allow for the fact that the average American works around 30 per cent more hours than his European counterpart.

In the US corner, we hear the same argument spun slightly differently: US workers put a lot more into their jobs than do work-shy Europeans.

The facts are quite clear. If we look at output per person, the US is miles ahead of Europe. If we focus instead on output per hour, the gap is much narrower. It could be that the average European is congenitally lazy or it could also be true that there aren't too many opportunities for us to work any more than we do (those unreconstructed sclerotic European economies shoulder the blame).

But we can be sure that the transatlantic economic gap could be closed if we could find a way to get Europeans to work harder and longer. For all of the flannel surrounding the Lisbon Agenda - which sets economic supremacy over the US by 2010 as its overriding ambition - this simple truth has been largely ignored.

An insight into how American businesses view the work ethic was recently gained via a conversation with a very upset Englishman in a City of London pub.

This acquaintance of mine works for a large American investment bank with its European headquarters in Canary Wharf. My friend is a senior member of a very successful equity research team and is fabulously well-rewarded for whatever it is that he does. By all relevant criteria, he thought he was doing well until he was summoned to a meeting with his bosses about two "issues".

The first problem related directly to his hours of work - there are, his superiors suggest, simply not enough of them.

How did they arrive at this conclusion?

Like most offices these days, entry and exit to the steel and glass premises of this particular megabank is gained via the use of a swipe card. Data gained from the use of this card is fed into a central computer and is used to compile statistics about the working habits of the bank's employees. The average time of day that my friend leaves the office was causing palpitations in the executive suite (average start time was not, apparently, a problem).

The second issue related to the use of a company-issued Blackberry smart phone (for the uninitiated, this device permits mobile access to email and has been a huge hit with the suits). Megabank was disturbed to find that my friend was using his Blackberry to read his work-related email very infrequently.

He was told in no uncertain terms that he has been given this device to facilitate working in the evenings and at weekends. Again, he was flabbergasted by the extent to which his working life was being electronically monitored.

There are various ways we could respond to all of this. We could accept that a macho work ethic has always prevailed in the City, and that the Americans have simply taken things to the next stage.

We could observe the lunacy of pursuing quantity over quality: there is nothing in this tale of the quality of the worker's output, merely a focus on how many hours he spends in the office. By contrast to all of this, in many European cities the weekend rush hour now begins at 3 p.m. on a Thursday - and Monday morning traffic is blissfully quiet.

It is clear that US firms are different, particularly those in the financial sector. Accepting that the examples cited here are probably extreme - even by American standards - it would be interesting to observe how this story would be received by a group of US, European and British executives.

I expect the Americans would shrug and mutter something about surly and ungrateful Europeans.

Continental executives would fume over the inappropriate work/life balance imposed by US firms and be secretly jealous of the power of their American counterparts.

British executives, while waiting to be formally introduced, would silently remind themselves to get a second jacket cut the next time they visited their tailor (to leave on the back of their chair when out for a long lunch).

Just how we view these profound differences probably depends on where we live. I suspect that there is little sympathy for each other's business models. But the simple truths remain: Americans work harder and reap the rewards.