美国政府报告突出电脑黑客严重威胁美国经济大纲

U.S. officials say a new government report details the threat hackers pose to the nation's economy, with China a clear leader among countries carrying out cyber attacks.

Officials have described the classified "National Intelligence estimate" to U.S. media, including The Washington Post, which said late Sunday hackers are targeting the energy, finance, information technology, aerospace and automotive sectors.

Some estimates put the cost to the U.S. economy at tens of billions of dollars each year. But, with some companies reluctant to report when they are hacked, the true cost is not known.

The White House is weighing how to respond, with options including possible trade actions and visa restrictions. The Washington Post says President Barack Obama is expected to issue an executive order on cyber security this week aimed at helping the private sector protect against hacking attempts.美国官员说，政府发表的一份新政府报告详细说明了电脑黑客对美国经济构成的威胁，在从事网络入侵活动的国家里，中国明显居于首位。

美国官员向包括华盛顿邮报在内的美国媒体说明了加密的“国家情报机构对电脑黑客威胁的评估情况”。华盛顿邮报星期天晚间说， 电脑黑客入侵能源、财经、信息技术、航天以及汽车制造等部门的网站。

一些评估结果显示，电脑黑客每年对美国经济造成的损失为数百亿美元。但一些公司在网络遭到入侵后不愿报告，因此实际损失数字无从得知。

白宫目前正在考虑如何做出反应，选择方案包括采取贸易手段和实行签证限制。华盛顿邮报说，预计奥巴马总统本星期将就网络安全问题发表一项政令，协助保护私营企业的网络免遭电脑黑客入侵。