America: Washington's efforts to export democracy, freedom and market economics have been a mixed success in recent years and have done little to endear the world's only superpower to its neighbours and allies.
If America really wants to win hearts and cheer the world up a little, it should consider exporting the quality almost all its people share and all its visitors admire - good manners.
If you invite friends to dinner in Washington, they will not only arrive on time but will leave at a reasonable hour, usually following up with a handwritten letter of thanks.
American good manners go well beyond such etiquette, however, to a universally accepted code of consideration for others in even the most casual dealings. There are great regional variations, with Southerners employing more elaborate forms of address, referring to everyone as Sir or Ma'am regardless of position or status. Texans tip their hats, Southern Baptists wish you "a blessed day" and Californians avoid any action that might invade your personal space.
Even in New York, a city with a reputation for brusque behaviour if not downright rudeness, modern manners are an intricately worked out system for sharing a crowded space with millions of others.
Changes in technology, sexual mores and popular enthusiasms have created further new challenges for polite society however, and New York magazine this week treated its readers to a brand-new Urban Etiquette Handbook, eloquently subtitled "How not to be a Jerk".
It's full of useful advice about everything from talking in elevators to stealing a cab, smoking cannabis at a party and the proper way to behave while travelling by subway. Here the rules are clear - no eating, knees no more than six inches apart, don't ogle fellow passengers for more than two seconds at a time - and if you're wearing low-risers, hoist them up rather than expose the rest of us to your bottom cleavage.
Dating etiquette has changed little over the years and the rule is that whoever does the asking does the paying - unless the asker is a woman, in which case the man pays.
A new dilemma has emerged for the thousands of couples who have met online - at what point should you take down your personal ad or profile? The answer is, apparently, not until you've both agreed that you are in an exclusive, monogamous relationship.
Office life is full of social minefields, such as the sight of a colleague crying (the proper response to which is an empathetic wince but no words of comfort) and how to put an end to an email exchange.
And is it ever acceptable to talk to a stranger on an elevator? "If there are six or fewer people on the elevator, no. However, if the group is larger than six, you have achieved an Elevator Humour Quorum and someone must make a remark about the elevator's lack of size or speed in order to relieve the tension created by standing in a tiny space with six or more strangers. If another member of the group makes the remark first, Elevator Humour Solidarity obliges you to chuckle mildly," says the New York handbook.
As for mobile phones, they should never be used in cinemas, quiet restaurants, during dinner parties or dates or during any commercial transaction. Look at waiters when ordering from them, always tip 20 per cent unless something disastrous has happened and if you are splitting a bill, do it evenly.
"The exchange of witty, flirtatious banter is admittedly the e-mail quagmire with the fewest number of obvious exit strategies. Nonetheless, it should be resolved like real-time, witty, flirtatious banter: with one party either summoning the courage to ask for a date or ending the quasi-relationship by means of unexplained unresponsiveness," the handbook says.