My answer

一个小问题 为什么他们不敦促美国政府立即释放萨达姆和米洛舍维其 并停止追捕拉登呢? 拉登被抓住后也难逃一死吧

Then are not in the hands of US, but being held by international martial court. US probably has the dominating influence on the issue. But the international martial court would not execute them for humanitarian reasons. For the same reasons, humanitarian organization is asking China to do the same.
It does not make the whole world much better by acting more barbaric than barbarians.
See my point? US and humanitarian organization are not trying to persuade China release the criminal, but persuading China handle the issue in a more human manner. Of course, China doesn’t have to follow that. What is big deal in killing? Especially, that guy sounds deserving that end and the execution of him would surely wins the support of ordinary people.