It’s easy, dramatic, and proper for Condoleezza Rice and Nicholas Sarkozy to rail against the world’s failure to do anything in Darfur. But there are many reasons why that has proved so hard, and none of them will disappear because of this week’s grandstanding.

“Silence kills,” said the new French President at an international conference in Paris. He declared that “we want to mobilise the international community to say ‘That’s enough’.”

In four years more than 200,000 people have died in Darfur and more than two million are thought to have become refugees, in a hugely complex conflict that has pitted ethnic groups against each other and rebels against the Government. The Khartoum regime is accused of raising a brutal militia of Arab nomads called the janjawid to crush the rebels, which it denies.

The world “cannot continue to sit by”, said the US Secretary of State. But it hasn’t; the past two years are a chronicle of failed peace talks, running up against the same obstacles time after time. At this point, sitting by is all that is left, unless the problems are overcome.

— The West, China, Russia and Japan do not want to invade Sudan to stop the killing. At the G8 summit of industrial powers earlier this month, the eight leaders said that “we underline that there is no military solution to the conflict in Darfur”.

— It follows that any international role – even sending in a peacekeeping force – will either need the consent of the Khartoum regime, or, possibly, the intervention of the African Union (a group of more than 50 African states with fragile dreams of acting like a unified force).

— Khartoum is not going to give that consent without more pressure. It was not even invited to the Paris talks, on the ground that they were designed to rally international support, not to discuss “peacemaking”. But as Rice pointed out, “Sudan has a history of agreeing to things and then trying to change them or to backtrack.”

— It is impossible to put on more pressure through United Nations sanctions without the support of China. But China, which buys 65 per cent of Sudan’s oil production, and sells it weapons, has refused to back proposals for sanctions in the UN Security Council. It was encouraging that China took part in the Paris meeting – but it simply repeated its opposition. “Now is not the time to talk about further sanctions,” said Lu Giujin, China’s special envoy for Sudan. When Ban Ki Moon, the UN Secretary-General, said that China had played a “constructive role” in the process, and that he was “satisfied” with its contribution, he was being polite to the point of dissembling, or has standards which are inhumanely low.

— The African Union force of 7,000 has been overwhelmed in trying to stop the turmoil. It doesn’t help that soldiers haven’t been paid recently, as the Paris meeting acknowledged – but for all the pledges of more money, that isn’t the biggest problem. It was not helpful that the African Union stayed away from the meeting, calling it a distraction.

— The agreement between Khartoum and the UN earlier this month for a “hybrid force” of the UN and African Union remains vague. France’s view this week that its forces would probably be the largest contingent is encouraging. But plans for deployment are failing to move forward in the bickering.If there are two obstacles above all others, they are China and money. The Paris meeting took a tiny step towards climbing each of those, but not enough. As things stand, the next round of talks between opposing sides, set for August, will run into the same wall.

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