The word from the White House went out to senior U.S. officials months before President Trump landed in Beijing on Wednesday: Avoid unnecessary confrontations with China, large or small, that could interfere with Mr. Trump’s effort at rapprochement with America’s largest military, economic and technological competitor.

在特朗普总统周三抵达北京的几个月前，白宫向美国高级官员传达了指示：避免与中国发生任何不必要的对抗，无论规模大小，以免干扰特朗普与这个美国最大的军事、经济和技术竞争对手改善关系的努力。

It did not work out that way.

但事与愿违。

Over the past few weeks, the Treasury Department has put new sanctions on Chinese firms it said provided targeting data to Iran that enabled strikes on bases across the Middle East that did billions of dollars in damage to American facilities. The White House has accused China of stealing artificial intelligence models from U.S. tech companies. And just this week, federal prosecutors said they had charged a California mayor with illegally working for Beijing.

过去几周里，美国财政部对一些中国企业实施了新的制裁，称这些企业向伊朗提供了目标数据，使伊朗得以对中东各地的基地发动袭击，对美国设施造成了数十亿美元的损失。白宫指责中国从美国科技公司窃取人工智能模型。就在本周，联邦检察官表示，他们已起诉加州的一名市长非法为北京工作。

There have been actions against midsize oil importers in China for secretly buying up Iranian oil. The only big step that the administration delayed was final approval of a $13 billion military aid package for Taiwan, which the White House designed but will not fulfill until Mr. Trump is back. That leaves President Xi Jinping time to voice his objections.

政府还针对中国秘密购买伊朗石油的中型石油进口商采取了行动。政府唯一推迟的重大举措是对一项价值130亿美元的对台军事援助计划的最终批准，该计划由白宫主导设计，但在特朗普回国之前不会落实。这给中国国家主席习近平留出了表达反对意见的时间。

It is not clear why there has been such a sudden deluge of China measures, other than the fact that the Trump administration has been in office for nearly a year and a half. That is enough time for the China hawks appointed by Mr. Trump, and there are plenty, to gather evidence and build a case. Sometimes, that means forcing the president to see the evidence of Chinese-led actions designed to undermine the United States or its allies, even if his first instinct is to explain what a “good relationship” he has with Mr. Xi and seemingly suggest that all might be forgiven.

目前尚不清楚为什么突然涌现出那么多针对中国的措施，唯一可以解释的是特朗普政府上任已近一年半这个事实。这段时间足以让特朗普任命的众多对华鹰派人士收集证据并建立案件。有时，这意味着迫使总统看清由中国主导的、旨在削弱美国或其盟友行动的证据，即使他的第一直觉是解释他与习近平有着多么“良好的关系”，并且似乎表示一切都可以被原谅。

Indeed, Mr. Trump struck a largely conciliatory tone Thursday, telling Mr. Xi that he is “a great leader” and that “it is an honor to be your friend.” For his part, Mr. Xi warned Mr. Trump that “conflicts” between the two superpowers could occur over the issue of Taiwan.

事实上，特朗普在周四主要采用和解的基调，称习近平是“伟大的领导人”，还说“很荣幸能成为你的朋友”。习近平则警告特朗普，两个超级大国之间可能会围绕台湾问题发生“冲突”。

尽管习近平警告中美之间可能出现“冲突”，特朗普周四仍采取了和解的姿态。

Some experts said it was unlikely that the Trump administration was trying to gain leverage over China during the talks this week with its flurry of tough actions, as many of them amounted to little more than accusations that Beijing readily denies. Instead, senior officials may be seizing a perceived opportunity to highlight tensions with China over Iran, cybersecurity and artificial intelligence — and remind the president that Beijing, in addition to posing the biggest geopolitical threat to the United States, has not decided to start playing nice.

一些专家表示，特朗普政府不太可能试图通过这一连串强硬行动在本周的谈判中获得筹码，因为其中许多行动不过是北京轻易就否认的指控。相反，高级官员们可能是在抓住一个他们眼中的机会，以便凸显在伊朗、网络安全和人工智能问题上与中国的紧张关系——并提醒总统，北京不仅对美国构成最大的地缘政治威胁，而且并未决定开始展现出友善姿态。

Chinese companies, for example, have been discussing arms sales with Iran, plotting to send the weapons through other countries to mask the origins of the military aid, The New York Times reported this week.

例如，《纽约时报》本周报道称，中国企业一直在与伊朗讨论武器销售事宜，密谋通过其他国家运送武器，以掩盖军事援助的来源。

But the Iran war is just the latest irritant for U.S. national security officials. Chinese hackers continue to breach U.S. government and corporate systems with little consequence. The F.B.I. recently identified what it believed were Chinese hackers inside a database it maintains on its domestic surveillance orders. That discovery was especially alarming because Beijing appeared to be building on its past success of infiltrating the bureau’s internal networks by doing so again.

但伊朗战争只是令美国国家安全官员头疼的最新困扰。中国黑客持续入侵美国政府和企业系统，几乎没有承担什么后果。美国联邦调查局最近在其维护的一个关于该局国内监控命令的数据库中，发现了据信是中国黑客的踪迹。这一发现尤其令人担忧，因为北京似乎是在过去成功渗透该局内部网络的基础上，再次故伎重演。

“I see this as the hawkish officials pushing on areas where they think the door is the most open right ahead of the summit,” said Elizabeth Economy, a senior fellow at the Hoover Institution at Stanford and a former China adviser at the Commerce Department during the Biden administration. In many ways, Mr. Trump himself may be as much the intended audience as the Chinese, she said. “These are all areas where the president himself has placed a high degree of priority.”

“我认为，这是鹰派官员在峰会即将召开之际针对他们认为最有可能取得突破的领域施加压力，”斯坦福大学胡佛研究所高级研究员、曾在拜登政府商务部担任中国事务顾问的易明(Elizabeth Economy)说。她表示，在许多方面，和中国人一样，特朗普本人可能也是这些行动想要影响的对象。“这些都是总统本人高度重视的领域。”

In late April, amid rapidly rising fears in both Washington and Silicon Valley about the threats posed by advanced artificial intelligence breakthroughs, the White House published a memo written by Michael Kratsios, the science and technology adviser to the president, accusing China of “exploiting American expertise and innovation” by stealing proprietary A.I. technology to build its own models.

4月下旬，在华盛顿和硅谷对先进人工智能突破所带来的威胁日益担忧之际，白宫发布了由总统科技顾问迈克尔·克拉齐奥斯撰写的一份备忘录，指责中国通过窃取专有的人工智能技术来建立自己的模型，从而“利用美国的专业知识和创新”。

“Foreign entities principally based in China are engaged in deliberate, industrial-scale campaigns to distill frontier A.I. systems,” Mr. Kratsios wrote. Distillation is the term used to describe training smaller A.I. models off larger, more expensive ones to achieve similar capabilities.

“主要位于中国的外国实体正在进行蓄意的、工业规模的运动，对前沿人工智能系统进行蒸馏，”克拉齐奥斯写道。“蒸馏”是一个术语，用于描述利用更大、更昂贵的模型来训练较小的人工智能模型，从而实现类似的能力。

英伟达首席执行官黄仁勋是此次随特朗普出访的科技公司高管之一。

Also last month, a U.S. cybersecurity bulletin issued with security agencies in Britain, Japan and other allied countries highlighted evolving tactics from Chinese state-sponsored hackers who rely on vast networks of compromised devices to engage in cyberespionage and target vulnerable critical infrastructure systems. The alert came after a prolonged stretch during which Chinese cyberthreats were seldom highlighted by U.S. agencies, even as China’s hackers once again breached a sensitive internal network at the F.B.I. that stores information about the bureau’s surveillance targets.

同样在上个月，美国与英国、日本及其他盟国的安全机构联合发布的一份网络安全公告强调，受中国国家支持的黑客正采用不断演变的策略，依靠庞大的受感染设备网络从事网络间谍活动，并针对存在漏洞的关键基础设施系统。此次警告发布之前，美国机构在很长一段时间内很少强调来自中国的网络威胁，尽管在此期间中国黑客曾再次入侵联邦调查局一个存储其监控目标信息的敏感内部网络。

In yet another example from late March, the Federal Communications Commission issued an order to ban the import of new consumer routers manufactured overseas, citing cybersecurity risks, though it exempted existing routers. Some of the best-selling routers in the United States are built in China, including those produced by TP-Link, the largest producer of U.S. consumer and small-business routers. Actions against TP-Link, which was established in China but has a business unit in California responsible for international operations, had long been discussed among U.S. officials in multiple agencies but had been on pause for many months until the F.C.C. order came down.

还有一个例子是，3月下旬，联邦通信委员会以网络安全风险为由发布命令，禁止进口在海外制造的新型家用路由器，尽管现有路由器获得了豁免。美国市场上部分最畅销的路由器是在中国制造的，包括美国家用和小型企业路由器的最大生产者TP-Link的产品。TP-Link在中国成立，但在加州设有一个负责国际业务的业务部门，针对该公司的行动早已在美国多个机构的官员中讨论多时，但搁置了数月之久，直到联邦通信委员会的命令下达。

And just Friday, the State Department issued sanctions against several Chinese companies for providing satellite imagery to Iran that it said aided Tehran’s attacks against U.S. forces in the Middle East.

就在上周五，国务院对几家中国公司实施了制裁，原因是它们向伊朗提供卫星图像，称此举助长了德黑兰针对中东地区美军的袭击。

Then on Monday, federal prosecutors announced they had charged Eileen Wang, the mayor of Arcadia, Calif., with acting as an illegal agent of the Chinese government. An unsealed plea deal said Ms. Wang would plead guilty to the charge.

随后在周一，联邦检察官宣布起诉加利福尼亚州阿卡迪亚市市长王艾琳，指控她充当中国政府的非法代理人。一份解封的认罪协议显示，王艾琳将对该指控认罪。

“This plea agreement is the latest success in our determination to defend the homeland against China’s efforts to corrupt our institutions,” Bill Essayli, the first assistant U.S. attorney for the Central District of California, said in a statement. The timing of charges, just days before the summit, may have been coincidental, but was hard to ignore.

加州中区第一助理联邦检察官比尔·埃塞利在声明中表示：“这份认罪协议是我们决心捍卫祖国、抵御中国企图腐蚀我国体制的最新成功。”起诉的时间刚好在峰会前几天，这也许是巧合，但很难让人忽视。

The surge in action around China followed months of U.S. officials in the Trump administration downplaying the rivalry, so much so that the National Defense Strategy published in January offered a softer tone about seeking “respectful relations with China.”

围绕中国采取的行动激增之前，特朗普政府官员数月来一直淡化中美竞争关系，甚至在1月份发布的《国防战略》中声称寻求“与中国保持相互尊重的关系”，呈现出一种更为温和的基调。

The guidance from the White House in the run-up to the trip to avoid unnecessary confrontations, which was described by Trump administration officials, represents standard advice ahead of a high-stakes presidential visit.

特朗普政府官员称，白宫的出访前避免不必要对抗的指导意见是总统在进行事关重大的出访之前的标准建议。

But to read through the Pentagon’s reports on China is to get a picture of the pace of the Chinese naval and nuclear buildups and the relentless pressure on both the Philippines and Taiwan. It lists simulated blockade actions against Taiwan — something that may look more attractive to the Chinese government now that the United States is blockading shipments in and out of Iran. And it describes an unyielding effort to pursue artificial intelligence and “achieve self-sufficiency in semiconductors.”

但是，通读五角大楼关于中国的报告，就能了解到中国海军和核力量建设的步伐，以及中国对菲律宾和台湾不断施加的压力。这份报告列举了针对台湾的模拟封锁行动——鉴于美国目前正在封锁进出伊朗的货物，这种做法现在对中国政府可能显得更具吸引力。报告还描述了中国在追求人工智能和“实现半导体自给自足”方面不屈不挠的努力。

Mr. Trump did not mention the sanctions on Thursday, at least in public. But those sanctions — and mirrored efforts by China against the United States and its companies — may do more to define the relationship over the next few years than pronouncements of impending partnerships that are likely to be cited by Mr. Trump and Mr. Xi.

特朗普在周四没有提及这些制裁，至少在公开场合没有。但这些制裁以及中国针对美国及其公司采取的对等反制行动，或许比特朗普和习近平可能宣称的关于即将建立伙伴关系的声明，更能定义未来几年的两国关系。