Last week China's leader, Hu Jintao, provided Sudan with an interest-free loan to build a presidential palace. With that gesture, Hu demonstrated his contempt for the Western understanding of the world — and for Western policy toward his own country.

Sudan, you will recall, is the scene of the Darfur genocide. Since the killing began three years ago, the United States and its allies have flown in food and medicines, provided logistical help and money for a token African peacekeeping force, and done their best to isolate the Sudanese regime, which orchestrates the massacres. They have done this not because they have a selfish interest in Darfur but because tossing babies into bonfires is a crime against humanity.

In the run-up to Hu's visit to Sudan on Friday and Saturday, there were hopes that the Chinese leader would back the West's Sudan policy.

China's diplomats are forever reassuring the world about their country's "peaceful rise," and Hu duly expressed support for an expanded peacekeeping force in Darfur. But everything else about his visit demonstrated the gap between Chinese and Western priorities.

Hu called on nations to "respect the sovereignty of Sudan." But since the end of the Cold War, the Western view of sovereignty has grown increasingly contingent. If a nation slaughters its civilians (think Rwanda, Kosovo), harbors terrorists (Afghanistan) or refuses to cooperate with U.N. weapons inspectors (yes, Iraq), it forfeits its right to sovereignty. It may not be invaded, but it certainly can expect to face sanctions.

Sudan, by these standards, is an easy candidate for sanctions. But China's talk of "sovereignty" is code for the opposite policy. As well as paying for a presidential palace, Hu used his trip to cancel $80 million of Sudanese debt, to announce a plan to build a railway line and to visit an oil refinery that China partly owns, basking in the fact that 80 percent of Sudan's oil goes to his country.

Hu's visit was a statement that, in the Chinese view of the world, the principle of sovereignty trumps even the most appalling human rights abuses: It brushed aside the memory of the Rwandan genocide and the Holocaust. But at the same time, Hu was saying more than that. He was advancing an understanding of modernization that the West discarded 15 years ago.

By pursuing commercial ties with Sudan, Hu was implicitly saying that economic development comes first and that political development is unimportant. This was once the view of Western development organizations, which financed projects in health, education, infrastructure and so on — but steered clear of human rights, corruption and anything else that could be deemed "political." But in the early 1990s, the Western approach changed. Development experts pointed out that independent courts and newspapers help to limit corruption and so make economic development possible. In the absence of minimal political accountability, aid money is stolen. Rather than helping Africa's poor, it is siphoned off to pay for presidential palaces.

China is not financing a presidential palace by mistake; it is doing so deliberately. It is not financing just any presidential palace; it has chosen a president so odious that his fellow African leaders hold their noses at him. But this gesture is only the tip of the iceberg. To read the accounts of Hu's Africa visit in China's People's Daily is to recall Western development thinking of a half a century ago. "From 1995 to 2003, China administered 43 sessions of the 'Advanced Education and Scientific Research Program' in 21 African countries," the paper's online version crowed over the weekend. Development, in this conception, is all about technical transfers. Politics plays no part.

This Chinese understanding of development threatens to undermine the Western one. Western development aid is increasingly linked to measures of good governance, and investment from Western corporations and banks comes with conditions designed to ensure that ordinary people benefit. This promising advance cannot succeed if African dictators can ignore Western conditions with Chinese assistance.

But there is a more disturbing question: What does China's policy toward Sudan say about the West's policy toward China? The West is engaging with China on the theory that economic modernization will bring political modernization as well; otherwise, the West would merely be assisting the development of a communist adversary. China's Sudan policy is an assertion that this link between economic and political modernization is by no means inevitable, even in the extreme case. You can construct oil refineries, educate scientists, build ambitious new railways — and simultaneously pursue a policy of genocide.

Sebastian Mallaby is a member of The Washington Post's editorial page staff.