That there is a sense of cynicism about this latest bounty from the Gates software fortune may have to do with the trial under way in Washington DC. The mighty Microsoft is accused of breaking the rules to squeeze out rivals in the computer industry. What better time to display generosity than when the Microsoft brand is being battered from left and right?
All Americans understand that giving away money is not always the altruistic act it seems. For every charitable donation, the giver can expect giant tax benefits. Shell out $1bn (pounds 600m) and your deductions will be worth $600m.
Above all, it is a matter of expectations. In a tradition that was established by the industrial barons of the turn of the century, such as the steel giant Andrew Carnegie, the very wealthy of American are under an unwritten obligation to give.
Until recently, indeed, Mr Gates was suffering criticism that he was not doing enough to ensure the spread of his booty. When Ted Turner, founder of CNN, created a foundation to benefit the United Nations worth $1bn last year, he challenged Mr Gates to speed up his charitable donations.
This is an era where giving in America is reaching unprecedented heights. As more and more Americans find they have more money than they know what to do with - thanks to a seven-year boom in the economy and a meteoric stock market - private charitable foundations are being created at a record pace. Last year, the value of charitable donations reached 2 per cent of US GDP, which stands at $8trillion. It helps that there are 200 billionaires in the US today.
Gates has promised eventually to give away 90 per cent of whatever fortune he accumulates. His philanthropy so far is directed through two foundations. The William H Gates Foundation, established in 1994, is directed at giving to multiple causes such as education and healthcare. Last year he also set up the Gates Library Foundation to provide computer technology to libraries in poorer neighbourhoods.
The same culture of tycoons embracing philanthropy does not appear to exist in Britain, according to those involved in fund-raising for charities and the arts. There are, of course, exceptions. Vivien Duffield, daughter of the entrepreneur Charles Clore, has given away almost pounds 90m to medical charities, the arts and education. And John Paul Getty, American born but a British citizen since last year, was given a knighthood in recognition of the pounds 120m he has handed out.
In October Peter Lampl, who made his money in the equity markets, announced prep schools would be given pounds 40m by his charity, the Sutton Trust. We now also have the Rupert Murdoch chair of communications at Worcester, Oxford; Sir John Moores University in Liverpool; and the Sainsbury wing of the National Gallery.
But Mark Thorne, of Wealthwatch, which monitors donations by the rich in Britain, said: "The Americans get a great deal of kudos and prestige from the act of large donations. In Britain the wealthy are almost shy of such publicity."
Paul Brown, of the Association for Business Sponsorship of the Arts, blames the difference in tax systems. "In America the tax system is positively geared towards encouraging donations. Here it is just too complicated."
Top Ten Donors
1. Ted Turner - $1bn (pounds 625m) (US). Founder of CNN, Turner is now vice-chairman of Time Warner, the world's biggest media conglomerate. Married to the actress Jane Fonda.
2. Kathryn Albertson - $660m (pounds 412.5m) (US). Late husband Joe founded Albertson's supermarket chain, the US equivalent of Sainsbury's.
3. George Soros - $540m (pounds 337.5m) (US). Highly successful international currency speculator, currently based in New York. His interests include the legalisation of cannabis for medical purposes.
4. Bill Gates - $210m (pounds 131m) (US). Owner of Microsoft, Gates is fighting the US government over his firm's alleged monopoly status.
5. Leonard Abramson - $100m (pounds 62.5m) (US). Founder of US Healthcare, the US hospital network, which he sold in 1996. He funds cancer research.
6. Michael and Jane Eisner $89m (pounds 55.6m) (US). He is chair and CEO of the Walt Disney Corporation, one of world's biggest entertainment companies. Particularly concerned with helping underprivileged children in southern California.
7. Mitchell Wolfson Jr - $75m (pounds 47m) (US). Fortune from father's entertainment company. Collects historical memorabilia and has early braille edition of Mein Kampf.
8. Phyllis Wattis - $70m (pounds 44m) (US). The 92-year-old great grand-daughter of Brigham Young, founder of the polygamist Morman Church. She directs much of her charitable effort towards the support of museums.
9. Peter Lampl - $64m (pounds 40m) (UK). Sole Briton on the list, on strength of his charitable donations in past year.
10. Raymond Nasher - $50m (pounds 31m) (US). Dallas property developer, 75. Supports foundation dedicated to building a museum - to house his own art collection.Reuse content