Friday, February 02, 2007

Space wars

I have an editorial piece on news@nature on China’s recent missile destruction of a satellite. The commentary in the scientific press has had much to say about the possible hazards of the space debris this created, but less about the implications and significance of the act for space militarization. This is my take on that.

Published online: 24 January 2007; doi:10.1038/news070122-8 A dangerous game in space
Is China's satellite zapping simply old-fashioned sabre-rattling? Or is it a rational step to restrict the use of space weapons?

How do you reconcile China's shooting down of a satellite earlier this month with the subsequent insistence by its foreign ministry spokesman, Liu Jianchao, that China opposes military competition in space?

China has not yet explained its objectives. But the action makes perfect sense in the context of game theory, the conventional framework for analysing conflict and cooperation.

Put simply, if you want to spur nations to collaborate in curbing space militarization, good intentions are not enough. You need to show that you can get tough if the need arises.

A benign interpretation of China's action, then, is that it might accomplish what years of talking have not: force the United States to negotiate an international treaty on space weaponry. Does China have such a specific goal in mind? Or does it merely wish to leave its options open in dealing with rebellious Taiwan?

These are dangerous questions. But it is worth bearing in mind that the Chinese test is at least consistent with a completely rational approach to securing international enforcement of the peaceful use of space.

The classic scenario to explore cooperation between nations using game theory is the Prisoner's Dilemma. Here, two players are each given the choice of cooperating with each other or betraying the other person (defecting), with different rewards or penalties for each potential outcome. Mutual cooperation is more beneficial to both players than is mutual defection. But temptation gets in the way: the player who defects against a cooperator wins the biggest prize of all.

Although the rational strategy in a one-off bout of the Prisoner's Dilemma is to defect, it runs against self-interest in repeated rounds. Then, the most successful way to play is often a 'tit-for-tat' strategy, in which a player will initially cooperate, then respond in kind to the other player's previous choice.

Robert Axelrod, the political scientist at the University of Michigan in Ann Arbor who pioneered the study of Prisoner's Dilemma strategies, points out that in the real world, players who follow the tit-for-tat strategy need to cultivate a reputation for toughness. Other players must know that provocation will be met with retaliation. In the case of China, the message could be that the militarization of space will not be prevented simply by condemning it, but rather by showing that you can and will play the game if necessary.

The real world is, of course, not a computer simulation, in which the agents are rational. Although game theory is studied in defence-policy circles, no one denies that it gives little more than a cartoon picture of international relations.

But in this case the model fits. China and Russia have been calling for years for a treaty to constrain space weapons. Not only have these calls been ignored by the United States, but last year the White House issued perhaps the most aggressive policy statement about space since the chilliest days of the Cold War. It stated baldly that the United States "will oppose the development of new legal regimes or other restrictions that seek to prohibit or limit US access to or use of space."

The document not only asserted the United States' right to pursue its "national interests" (including "foreign policy objectives") by preserving its "freedom of action" in space, but also threatened to deny adversaries the same freedom.

Is China an 'adversary'? Friendly overtures between NASA and the China National Space Administration might suggest otherwise, but NASA is not the Pentagon. The United States is not only still pursuing its national missile-defence programme but is also developing laser-based weapons that can knock out satellites from the ground or aircraft. It is hardly surprising then, that anyone who is serious about stopping such a relentless and defiant pursuit of space weaponry through international agreement will deploy the bullish lessons of game theory.

This is not to say that the Chinese test is defensible. It is understandable that its neighbours, such as Japan and Australia, should be dismayed by it, and that Taiwan should regard it as an act of aggression. And there is every chance that the United States will interpret it as the opening shot of an arms race rather than as a summons to the negotiating table.

China might think that keeping a strong hand relies on not making its intentions too explicit. All the same, there is a difference between developing space weapons at the same time as opposing the militarization of space, and developing weapons while refusing to ban them. Which would you prefer?


Anonymous said...

歐美a免費線上看,熊貓貼圖區,ec成人,聊天室080,aaa片免費看短片,dodo豆豆聊天室,一對一電話視訊聊天,自拍圖片集,走光露點,123456免費電影,本土自拍,美女裸體寫真,影片轉檔程式,成人視訊聊天,貼圖俱樂部,辣妹自拍影片,自拍電影免費下載,電話辣妹視訊,情色自拍貼圖,卡通做愛影片下載,日本辣妹自拍全裸,美女裸體模特兒,showlive影音聊天網,日本美女寫真,色情網,台灣自拍貼圖,情色貼圖貼片,百分百成人圖片 ,情色網站,a片網站,ukiss聊天室,卡通成人網,3級女星寫真,080 苗栗人聊天室,成人情色小說,免費成人片觀賞,

傑克論壇,維納斯成人用品,免費漫畫,內衣廣告美女,免費成人影城,a漫,國中女孩寫真自拍照片,ut男同志聊天室,女優,網友自拍,aa片免費看影片,玩美女人短片試看片,草莓論壇,kiss911貼圖片區,免費電影,免費成人,歐美 性感 美女 桌布,視訊交友高雄網,工藤靜香寫真集,金瓶梅免費影片,成人圖片 ,女明星裸體寫真,台灣處女貼圖貼片區,成人小遊戲,布蘭妮貼圖片區,美女視訊聊天,免費情色卡通短片,免費av18禁影片,小高聊天室,小老鼠論壇,免費a長片線上看,真愛love777聊天室,聊天ukiss,情色自拍貼圖,寵物女孩自拍網,免費a片下載,日本情色寫真,美女內衣秀,色情網,

Anonymous said...


女優王國,免費無碼a片,0800a片區,免費線上遊戲,無名正妹牆,成人圖片,寫真美女,av1688影音娛樂網,dodo豆豆聊天室,網拍模特兒,成人文學,免費試看a片,a片免費看,成人情色小說,美腿絲襪,影片下載,美女a片,人體寫真模特兒,熊貓成人貼,kiss情色,美女遊戲區,104 貼圖區,線上看,aaa片免費看影片,天堂情色,躺伯虎聊天室,洪爺情色網,kiss情色網,貼影區,雄貓貼圖,080苗栗人聊天室,都都成人站,尋夢園聊天室,a片線上觀看,無碼影片,情慾自拍,免費成人片,影音城論壇,情色成人,最新免費線上遊戲,a383影音城,美腿,色情寫真,xxx383成人視訊,視訊交友90739,av女優影片,