If you want to support the monks, then call Gary Player to account

China has become the world's excuse for inaction. If there is anything that a government or a business does not want to do, it invokes the Yellow Peril. Raise the minimum wage to £6 an hour? Not when the Chinese are paid £6 a year. Cap working time at 48 hours a week? The Chinese are working 48 hours a day. Cut greenhouse gas emissions? The Chinese are building a new power station every nanosecond. China has become our looking-glass bogeyman: if you behave well, the bogeyman will get you.

As we saw during George Bush's climate pantomime last week, China the excuse is not the same place as China the country. Bush insists that the United States cannot accept mandatory carbon cuts, because China and India would reject them. But while he stuck to his voluntary approach, China and India called for mandatory cuts. "China" is a projection of the west's worst practices.

I mention this because the western companies still trading with Burma use it as their first and last defence. If we withdraw, they insist, China will fill the gap. It is true that the Chinese government has offered the Burmese generals political protection in return for cheap resources. In January, for example, China vetoed a UN resolution condemning the junta's human rights record. Three days later it was given lucrative gas concessions in the Bay of Bengal. It is also true that the Chinese government has no interest in promoting democracy abroad. But the more the Burmese junta must rely on a single source of investment and protection, the more vulnerable it becomes. China is not intractable. If western governments boycotted the Beijing Olympics, it would precipitate the biggest political crisis in that country since 1989.

The businesses still working in Burma are having to scrape the barrel of excuses. Even Tony Blair, that bundle of corporate interests in human form, said: "We do not believe that trade is appropriate when the regime continues to suppress the basic human rights of its people." Explaining his company's decision to pull out of the country, the CEO of Reebok noted that "it's impossible to conduct business in Burma without supporting this regime. In fact, the junta's core funding derives from foreign investment and trade". As the junta either controls or takes a cut from most of the economy, and as almost half the tax foreign business generates is used to buy arms, any company working in Burma is helping to oppress the people.

The travel firms Asean Explorer and Pettitts, which take British tourists round the country in defiance of Aung San Suu Kyi's pleas, both refused to comment when I rang them, then slammed down the phone. Aquatic, a British company that provides services for gas and oil firms, was more polite, but still refused to talk. The tourism companies Audley Travel and Andrew Brock Travel Ltd promised to phone me back but failed to do so. But aside from invoking the Chinese bogeyman, each of the others I talked to produced a different justification.

The spokeswoman for Orient Express, a travel company that runs a cruiser on the Irrawaddy river and a hotel in Rangoon, told me that "tourism can be a catalyst for change". Given that tourism has continued throughout the junta's rule, I asked how effective that catalyst has been. "There has been very slow progress, but we feel it has helped." The Ultimate Travel Company explained that: "We feel we just like to offer the people who travel with us a choice. If people want to travel, they can. And really I'd prefer not to enter into a debate about it."

Rolls-Royce, which overhauls engines for Myanmar Airways, a company owned by the state, told me that it operates "in line with UK export licences ... As long as we are meeting government requirements, that's what we work to. I'm not getting into a debate on this issue. We're doing this to ensure passenger safety."

William Garvey, the boss of the furniture company that bears his name and that works mostly in Burmese teak, admitted that he buys timber "that comes from Rangoon, through government channels". But if he stopped, "a highly likely consequence is that the rate of felling would increase dramatically ... Whatever you may think about the Burmese government, they are still using a sustainable system for extracting teak." Aren't human rights a component of sustainability? "In the strict sense, no."

The managing director of Britannic Garden Furniture, which makes its benches from Burmese teak and supplies the royal parks and the Tower of London, told me: "I know it's no excuse to say we don't buy it directly ... You try and get teak from other sources. But it's rubbish ... The government has given us no directive not to trade with Burma."

All these companies have felt some pressure already, thanks to the work of The Burma Campaign UK, which includes them on its "dirty list". But I have stumbled across one western firm that most Burma campaigners appear to have missed. It is run by one of the world's most famous sportsmen, the golfer Gary Player. Player has made much of his ethical credentials. Next month he will host the Nelson Mandela Invitational golf tournament, whose purpose is "to make a difference in the lives of children". One of his websites shows a painting of Mr Player bathed in radiant light and surrounded by smiling children. Nelson Mandela stands behind him, lit by the same halo.

Golf, to most of us, looks like a harmless, if mysterious, activity, but in Burma it is a powerful symbol of oppression. Some of the country's courses have been built on land seized from peasant farmers, who were evicted without compensation. Golf is the sport of the generals, who conduct much of their business on the links.

Player's website shows him, in 2002, launching the "grand opening" of the golf course he designed, which turned "a 650-acre rice paddy into The Pride of Myanmar. The golfer's paradise that stands in Myanmar today is said to be living proof that miracles do happen." I asked his company the following questions. Who owned the land on which the course was constructed? How many people were evicted in order to build it? Was forced labour used in its construction? As Player's company is based in Florida, did the design of this course break US sanctions? His media spokesman told me: "The Gary Player Group has decided not to comment on any questions regarding Myanmar-Burma." It seems to me that there is a strong case for asking Nelson Mandela to remove his name from Mr Player's tournament.

If, like me, you have been shaking your head over the crushing of the protests, wondering what on earth you can do, I suggest you get on the phone to these companies, demanding, politely that they cut their ties. I sense that it wouldn't take much more pressure to persuade them to pull out. By itself, this won't bring down the regime. But it will cut its sources of income, and allow us to focus on confronting the reality of Chinese investment, rather than the excuse.

George Monbiot