Over lunch at the University of Texas at Austin, a professor from China and two Chinese students spoke dispiritedly this week of the directive issued by Secretary of State Marco Rubio to “aggressively revoke” visas of Chinese nationals studying in “critical fields.” They also talked about a Republican bill in Congress that would ban Chinese student visas to the United States.

本周，在得克萨斯大学奥斯汀分校吃午餐时，一名来自中国的教授和两名中国学生沮丧地谈到国务卿鲁比奥要求“大力撤销”在“关键领域”学习的中国公民签证的指令，以及国会的共和党人提出的一项禁止向中国学生发放赴美签证的法案。

Even if such matters never come to pass, said Xiaobo Lü, a professor of government at the university in Austin, “the damage is already being done.”

即使这些事情永远不会成真，奥斯汀大学的政府学教授吕晓波说，“损害已经造成了。”

“Chinese students are practical,” he said. “They now have to consider whether, if they come to America, their studies will be disrupted. There’s no removing that uncertainty. That ship has sailed.”

“中国学生很务实，”他说。“他们现在必须考虑，来美留学是否会遭遇学业中断。这种不确定性已经无法消除。木已成舟了。”

The two students accompanying Dr. Lü to lunch, who asked not to be named for fear that their visa status might be at risk, described several recent conversations with Chinese friends. One had decided to turn down offers at two prestigious American journalism schools and had opted instead for the program at the University of Hong Kong. Another said no to a coveted slot at the Massachusetts Institute of Technology in favor of a modest local government job.

陪同吕晓波午餐的两名学生介绍了最近与几个中国朋友的谈话情况。由于担心签证身份可能受到威胁，这两名学生要求不透露姓名。在那些中国朋友当中，有人决定拒绝两所美国著名新闻学院的录取通知，转而选择就读香港大学。还有一位拒绝了麻省理工学院令人向往的机会，转而选择了一份普通的地方政府工作。

A third Chinese friend, currently studying at Johns Hopkins University, is mulling whether to pack his bags and finish his degree back home.

另外一个目前就读于约翰·霍普金斯大学的中国朋友正在考虑是否要收拾行囊回国完成学业。

Their accounts align with sentiments shared by a senior academic official at the University of Texas, who said that several excellent graduate school candidates from China had withdrawn their applications. The official added that a number of Chinese students on the Austin campus were afraid to criticize the measures. He spoke on condition of anonymity because he shared those fears.

他们的说法与得克萨斯大学一名高级教务主管的看法一致，他表示，几名优秀的中国研究生申请者已经撤回了申请。这位官员还说，奥斯汀校区的一些中国学生不敢批评这些措施。他要求不透露姓名，因为他也有同样的担忧。

There are about 1,400 Chinese students on the Austin campus. A spokesman for the university said that its administrators would have no comment.

奥斯汀校区有大约1400名中国学生。学校的一名发言人表示，校方对此不予置评。

The chilling effect that has overtaken some Chinese nationals in the United States on student visas comes as the Trump administration and its allies have suggested that their presence constitutes a national security threat. Such assertions, combined with the continuing trade war with China, represent an increasingly strident anti-China sentiment among conservative officials, even as their states wrestle with the benefits and drawbacks of having Chinese students in their colleges and universities.

特朗普政府及其盟友把中国留学生渲染成国家安全威胁，这在一些持学生签证的中国公民当中引发了寒蝉效应。这样的指控，再加上与中国持续的贸易战，折射出保守派官员中日益尖锐的反华情绪，尽管他们所在的州仍在权衡招收中国学生的利弊得失。

The bill in Congress, called the Stop CCP Visas Act, was introduced in March by Representative Riley Moore, a freshman Republican from West Virginia who said in an interview that “we’re going to push hard for it.”

国会的这项法案名为《停止中共签证法案》，是由西弗吉尼亚州共和党众议员莱利·摩尔于今年3月提出的，他在接受采访时表示，“我们将努力推动这项法案。”

Its prospects in the House are uncertain, and it has little chance of passing in the Senate, where it would need Democratic support to achieve a filibuster-proof supermajority. The timing of the legislation is also curious, given that Chinese student enrollment in the United States has fallen by more than 25 percent, from about 370,000 in 2019 to roughly 277,000 in the 2023-24 academic year, according to data from the Institute of International Education.

该法案在众议院通过的前景尚不确定，在参议院获得通过的可能性也很小，因为它需要民主党的支持才能达成足以打破冗长辩论程序的压倒性多数票。提出这一立法的时机也颇为耐人寻味，因为根据国际教育协会的数据，在美中国学生的入学人数已经下降了25%以上，从2019年的约37万人下降到2023-24学年的约27.7万人。

Critics say that even if the bill goes nowhere, its message and Mr. Rubio’s directive will alienate foreign students who are considering the United States.

批评人士表示，即使该法案最终搁浅，其释放的信号和鲁比奥的指示都将吓退那些考虑来美国留学的外国学生。

“Why take the chance to come here when you know that some new policy might disrupt your studies?” said Eddie West, the assistant vice president for international affairs for California State University, Fresno. “And you could understand if a family in India is looking at this and saying, ‘Are we going to be targeted next?’”

“既然你知道一些新政策可能会中断你的学业，为什么还要冒险来这里呢？”加州州立大学弗雷斯诺分校负责国际事务的助理副校长埃迪·韦斯特说。“完全可以理解，一个印度家庭看到这些消息后可能会担忧，‘我们会成为下一个目标吗？’”

Of the Chinese citizens whose visas would be revoked by his bill, Mr. Moore was dismissive of the idea that they were here simply studying. “Maybe some are,” he said. He added that a law passed in 2017 by the Chinese government, the National Intelligence Law, stipulates that citizens living abroad must support their home country’s intelligence-gathering efforts. Of the estimated 15 percent of Chinese nationals who receive government scholarships to study abroad, Mr. Moore said, “They have to regularly report back to the diplomatic mission. They are active spies.”

对于那些签证将被他的法案吊销的中国公民，摩尔不认为他们来这里只是为了学习。“或许有个别例外，”他说。他还表示，中国政府2017年通过的《国家情报法》规定，居住在国外的公民有配合情报工作的义务。在获得政府奖学金出国留学的大约15%的中国公民中，摩尔说，“他们必须定期向外交使团汇报，他们是活跃的间谍。”

来自西弗吉尼亚州的共和党新生众议员莱利·摩尔提出了《停止中共签证法案》，该法案将禁止中国学生获得赴美签证。

Mr. Moore did not provide evidence to support his claims. The two University of Texas students, and eight other Chinese students and faculty members interviewed for this article, said they had never once interacted with their government back home, other than during the visa procurement process.

摩尔没有拿出证据来支持他的说法。这两名得克萨斯大学的学生，以及本文采访的另外八名中国学生和教职员工表示，除了签证申请，他们与中国政府没有任何接触。

Jessica Chen Weiss, a professor of China studies at Johns Hopkins University’s School of Advanced International Studies, said that a vast majority of Chinese students in the United States are not here to spy or obtain information for their government.

约翰·霍普金斯大学高级国际研究学院的中国研究教授白洁曦(Jessica Chen Weiss)表示，绝大多数在美国的中国学生不是来为政府从事间谍活动或搜集情报的。

“Chinese students who come to the United States want to stay and contribute,” she said, adding that three-quarters of Chinese graduate students in the fields of science, technology, engineering and math stay in the United States. The number is even higher for doctoral students in artificial intelligence, she noted.

“来美国的中国学生希望留下来做出贡献，”她说。她还指出，在科学、技术、工程和数学领域，四分之三的中国研究生留在了美国。她指出，人工智能博士生的比例甚至更高。

Representative Grace Meng, the New York Democrat and chairwoman of the Congressional Asian Pacific American Caucus, said in a statement that the legislation was “xenophobic and wrongheaded.” Ms. Meng pointed to a survey earlier this year by The Asian American Foundation that found more than one in four Americans viewed Chinese Americans as a threat to American society. She added that Mr. Moore’s initiative, if passed, “would send a dangerous message that people of Chinese descent — and Asian Americans more broadly — do not belong in this country.”

纽约州民主党众议员、国会亚太裔美国人核心小组主席孟昭文在声明中说，这项立法是“充满排外情绪且荒谬至极”。孟昭文指出，亚裔美国人基金会今年早些时候的一项调查发现，超过四分之一的美国人认为华裔美国人对美国社会构成威胁。她还说，摩尔的提案如果获得通过，“将发出一个危险的信息，即华裔——以及更广泛的亚裔美国人——不属于这个国家。”

Mr. Moore said that he had not discussed the extent of any threat posed by Chinese students with his state’s flagship college, West Virginia University, where around 130 Chinese students are enrolled. University officials declined to comment for this article.

摩尔表示，他还没有与该州的旗舰大学西弗吉尼亚大学讨论过中国学生构成威胁的程度，该校约有130名中国学生。该大学官员拒绝就本文发表评论。

One of the bill’s seven Republican cosponsors, Representative Brandon Gill of Texas, said in a statement that “it’s time we start taking seriously the threat of the Chinese Communist Party and the hundreds of thousands of students they send to American universities each year, many of whom have been traced back to its espionage operations.” The statement provided no evidence for that assertion.

该法案的七名共和党联署人之一、得克萨斯州众议员布兰登·吉尔在声明中说，“我们是时候开始认真对待中国共产党的威胁了，他们每年向美国大学派出数十万学生，其中许多人已被证实与中共的间谍活动有关。”但该声明未提供相关证据。

Along with Mr. Gill, five other cosponsors — Representatives Troy Nehls of Texas, Andy Ogles of Tennessee, Burgess Owens of Utah, Addison McDowell of North Carolina and Scott Perry of Pennsylvania — represent districts in states that Mr. Trump won in November. Senator Ashley Moody, Republican of Florida, where Mr. Trump was also victorious in November, introduced a similar bill in the Senate.

除了吉尔之外，其他五位联署人分别是得克萨斯州众议员特洛伊·内尔斯、田纳西州众议员安迪·奥格尔斯、犹他州众议员伯吉斯·欧文斯、北卡罗来纳州众议员艾迪森·麦克道尔和宾夕法尼亚州众议员斯科特·佩里——均来自特朗普在去年十一月大选中获胜的选区。佛罗里达州共和党参议员阿什利·穆迪在参议院提出了一项类似法案，该州也是特朗普获胜。

Each of these states has universities with large Chinese student populations, including the president’s alma mater, the University of Pennsylvania, with more than 2,000 Chinese students, according to the most recent public data.

根据最新的公开数据，这些州的多所大学拥有大量中国留学生，包括特朗普的母校宾夕法尼亚大学，那里有2000多名中国留学生。

纽约州民主党众议员、国会亚太裔核心小组主席孟昭文谴责这项立法“充满排外情绪且荒谬至极”。

“We’re literally skimming off the best and brightest China has to offer,” said Peter Lorge, a professor specializing in Chinese military history at Vanderbilt University, which has more than 700 Chinese students. “They’re fighting to come here, and their own country is struggling to get them to come back,” Mr. Lorge said. “The idea that we’d turn them away is baffling to me.”

“我们实际上是在挑选中国提供的最优秀、最聪明的人才，”有700多名中国学生的范德比尔特大学专门研究中国军事史的教授彼得·洛奇说。“他们争相来到这里，而他们自己的国家也在努力争取让他们回去，”洛奇说。“我们却把他们拒之门外，这实在令人费解。”

But Dr. Weiss of Johns Hopkins said that Mr. Moore’s bill could have unintended consequences for U.S. security. During the Red Scare era of the 1950s, she said, a leading rocket scientist, Qian Xuesen, “was prevented from continuing his scientific career in the United States,” even though he helped found the Jet Propulsion Laboratory at the California Institute of Technology.

但约翰霍普金斯大学的白洁曦说，摩尔的法案可能会对美国的安全产生相反的效果。她说，在20世纪50年代的红色恐慌时期，著名的火箭科学家钱学森“被禁止在美国继续他的科学生涯”，尽管他参与创建了加州理工学院的喷气推进实验室。

Instead, Mr. Qian returned to China, where he helped develop China’s ballistic missile system.

于是，钱学森回到了中国，在那里帮助开发了中国的弹道导弹系统。

Dr. Lü, the University of Texas government professor, also referred to the saga of Mr. Qian as an example of how the significant contributions by Chinese scholars can be imperiled by fixating on unsubstantiated suspicions. “It would be like a doctor treating a small skin rash on a shoulder,” he said, “by amputating the whole arm.”

得克萨斯大学政府学教授吕晓波也以钱学森的传奇经历为例，说明一味执着于未经证实的怀疑会使得中国学者的重大贡献遭到抹杀。“这就像医生为了治疗肩膀上的小皮疹，”他说，“而把整个手臂截肢。”