Um, you realize that Nature is a magazine, not a journal right? Yes they have peer review but they have a heavy vested interest in publishing exciting-but-possibly-wrong stuff, which they do all the time.
And if results were simply fabricated, peer review can't always catch that as others have said. Though sometimes it is obvious if someone is suddenly able to do something that others have been trying to do but failed, but they can't show WHY it worked for them and not for anyone else. Sometimes quality professional journals, especially in experimental sciences, will have higher peer review standards in that direction than a headline-oriented magazine like Nature.
You realize that there is effectively no difference between a government-denied chinese hacker and a "non official cover" spy right?
And if they aren't government-employed then this is the completely appropriate action.
In either case, I 'd say its better to get this out in the open where the justice system can work it through rather than just finger pointing. If they're not government-sponsored (as the Chinese claim) then the Chinese should be willing to pony up and extradite them! (The fundamental issue here is really that the line between government and non-government is defined in a very different way in the US and China, both in law and in practice. China is still a single-party rule, which makes it often a matter of semantics what is government and what is not.)
The root problem here is the companies that make the drugs that have known properties are refusing to sell them to the state for use in executions. How it is legal for the companies who sell the drugs to discriminate in this way I don't understand. I know WHY they are doing it... due to pressure from anti-death penalty activists. But how it is legal?
And just to be up-front, I'm actually anti-death-penalty. But forcing state officials to euthanize people in inhumane ways in order to make headlines does not seem... humane.
I think the basic problem is that we are not at war with country X.
I actually believe the basic bill of rights applies to the agents of government, not the people. i.e. it does not just protect these special people called "citizens", it restrains the government from certain actions, such as denial of due process of law, against any person. However, the general "rule of law" does not apply in a war zone. The problem is that we have become stupendously lax about exactly where the wars the US is currently fighting actually are. Are we at war with Pakistan? No, but we perform military strikes inside Pakistan without their consent. Are we a warlord or a modern country?