Thousands of protesters have mobbed the Olympic torch as it makes its way around the world to protest China's violent repression of demonstrators in Tibet — turning the 21-city torch tour into a public relations fiasco for Beijing.

Despicable as China's actions in Tibet may be, I would argue that protesters should take a larger view. They should realize that China has become the chief patron of the vilest regimes in the world — undercutting at almost every turn, and every place, the West's efforts to promote human rights.

How can the United States, Europe and the United Nations effectively isolate rogue states when China is more than willing to lend them money, buy their oil, sell arms and offer warm relations to almost anyone who asks, no matter how murderous or corrupt.

China manages all of this with a foreign-policy trope that at first seems perfectly benign. As Jiang Yu, spokesman for the Foreign Ministry, put it recently, "China always adopts a policy of non-interference."

Actually, this policy has proved to be perfectly pernicious. China chooses not to pass judgment on other nations' behavior. No matter how dangerous or malevolent a state may be, China stands ready to make a deal. The non-interference policy also offers a corollary benefit: China says no one has any right to judge how China behaves — even when it shoots demonstrators in Tibet.

Nowhere is this more visible than in Sudan.

China is the chief benefactor for Sudan's genocidal leaders. In violation of a U.N. arms embargo, Beijing provides the weapons and ammunition that President Omar al-Bashir uses to arm the militias that have slaughtered more than 200,000 people in Darfur.

China buys 90 percent of Sudan's oil exports and has given the regime more than $1 billion in so-called "concessional" loans. They come with low interest — or none at all, and China has been quick to forgive them altogether. All of this for a state that the rest of the world regards as a pariah.

You'd hardly think Bashir needs the extra money. After all, at $100 a barrel, his oil earns about $28 million a day. But then, Transparency International's world corruption index rates only six nations out of 179 more corrupt than Sudan.

Sudan is hardly the only questionable benefactor of Chinese largess. China remains Burma's most important ally. You may recall that Burma's military rulers ordered troops to shoot and kill dozens of Buddhist monks during pro-democracy demonstrations last fall. Once again, China buys oil and natural gas from Burma and sells weaponry to the junta.

And then there's Iran. In 2004, a few months after the United Nations found that Iran was secretly processing nuclear fuel that could, eventually, be enriched for use in nuclear weapons, China signed a $100 billion deal to import natural gas from Iran over the next 25 years. What is more, China provided much of the equipment Iran first used to process nuclear fuel — and trained Iran's nuclear technicians.

In recent years, China has voted in favor of several U.N. Security Council sanctions against Iran. But, working with Russia, Beijing has blocked more expansive sanctions that might have proved effective, arguing that they were not convinced Iran was pursuing nuclear weapons. But then last week, Iran announced that it was tripling the number of centrifuges used to enrich uranium, while once again disavowing any interest in nuclear weapons. As Javier Solano, the European Union's foreign policy chief, noted last month: "To construct a nuclear power plant takes 10 years. So why enrich uranium now, when there is no place to use it?"

In recent years, China has struck energy deals with Hugo Chavez in Venezuela. The Chinese have begun oil exploration in Cuba. They made a mineral-exploration deal with Robert Mugabe, the president of Zimbawe, who now appears to be stealing the presidential election there.

Meantime, China remains North Korea's closest friend and protector. China provides about 70 percent of the renegade state's food and nearly 80 percent of its fuel.

Who's left? Last year, the Bush administration imposed economic sanctions on three Chinese companies for selling missiles and weaponry to Syria. Last summer, China gave Daniel Ortega, Nicaragua's president, $30 million to build a power plant. And Belarus, the last barbarous dictatorship in central Europe, celebrates its warm ties with Beijing.

What has all of this gained China? Short-term energy security. But in many of these states, when the dictators and zealots fall from power, the governments that replace them are likely to regard China with distrust, resentment, anger — or worse.

Joel Brinkley is a former Pulitzer Prize-winning foreign correspondent for The New York Times and now a professor of journalism at Stanford University. He wrote this commentary for McClatchy-Tribune Information Services.