China escalated its diplomatic feud with Japan on Sunday by sending Coast Guard ships to patrol near islands the countries both claim, and warning Chinese students in the country about what it said were risks to their safety.

周日，中国派遣海警船在中日都声称拥有主权的岛屿附近巡逻，并警告在日中国留学生注意其所称的安全风险，从而进一步升级了两国的外交争端。

The escalation came after comments this month by Prime Minister Sanae Takaichi of Japan about Taiwan, a self-governed democracy that China considers part of its territory. Ms. Takaichi told the Japanese Parliament that a hypothetical Chinese attack on Taiwan could trigger a military response from Tokyo.

事态升级的导火索是日本首相高市早苗本月就台湾问题发表的言论。台湾是一个实行自治的民主政体，中国视其为领土的一部分。高市对日本国会表示，如果中国对台湾发动攻击，东京可能会做出军事回应。

On Friday, the Chinese Embassy in Tokyo warned its citizens against traveling to Japan because of what it described as serious safety risks. China did not provide evidence, but the warning could affect an important part of Japan’s tourism economy. Nearly seven million Chinese travelers visited the country last year, accounting for nearly one in five international tourists, according to Japan’s tourism bureau.

周五，中国驻东京大使馆以所谓严重的安全风险为由，警告国民避免前往日本。中方并未提供证据，但这可能会对日本旅游业造成重大影响。据日本观光局统计，去年近700万中国游客到访日本，占国际游客总数的近五分之一。

On Sunday, China’s Coast Guard said that some of its ships were patrolling the waters of uninhabited islands — known as Diaoyu in China and Senkaku in Japan — that Japan controls but China also claims. The islands are north of Japan's westernmost islands and near Taiwan.

中国海警周日表示，派出多艘舰艇在钓鱼岛周边海域开展巡航。这些无人居住的岛屿（中方称为钓鱼岛，而日方称尖阁诸岛）目前由日本实际控制，但中国也提出主权主张。该岛群位于日本最西端诸岛以北，靠近台湾海域。

China regularly conducts what it describes as “rights enforcement patrols” in waters around the islands, but the latest patrol announcement was the first since Ms. Takaichi’s Taiwan comments.

中国经常在这些岛屿周围水域进行所谓“维权巡航”，但这是高市发表涉台言论后中国第一次发布巡航公告。

China’s Education Ministry also warned Chinese students on Sunday to “carefully plan” their study arrangements in Japan. The ministry said, without providing evidence, that there had been recent crimes against Chinese citizens and that safety risks were rising.

中国教育部周日亦提醒中国留学生“谨慎规划”赴日留学事宜。教育部在未提供证据的情况下称近期发生了多起针对中国公民的犯罪事件，安全风险正在上升。

上个月，日本首相高市早苗和中国领导人习近平在韩国庆州举行会晤。

This month’s feud ended what had been a brief diplomatic honeymoon between the two countries. Ms. Takaichi, a conservative prime minister who has been in office for less than a month, had a warm meeting with China’s top leader, Xi Jinping, last month in South Korea.

本月的争端结束了两国短暂的外交蜜月期。高市早苗这位保守派首相上任不足一个月，上个月还在韩国与中国最高领导人习近平进行了友好会晤。

Relations between China and Japan have for decades been prone to flare-ups, fueled largely by atrocities the Japanese army committed in China, including the Nanjing Massacre in 1937, for which Beijing believes Tokyo has never sufficiently apologized.

数十年来，中日关系一直容易因历史问题出现紧张，主要源自日本军队在中国犯下的暴行，包括1937年的南京大屠杀，北京认为东京从未就此做出充分的道歉。

Ms. Takaichi’s Nov. 7 comments in Parliament were not a significant revision of Japan’s longstanding position of support for Taiwan. But they broke with previous Japanese policy of avoiding any explicit mention of the island in the context of “survival-threatening situations” — a classification that, under Japanese law, allows the deployment of the country’s military.

高市11月7日在国会的发言并未对日本长期以来支持台湾的立场做出重大修正，但打破了日本以往在涉及“存亡危机事态”问题上刻意回避明确提及台湾的做法。根据日本法律，此类事态认定允许日本自卫队进行军事部署。

Like the United States, its close military ally, Japan has long adopted a policy of strategic ambiguity that leaves its intentions vague regarding any future Chinese military attack on Taiwan.

与其亲密的军事盟友美国一样，日本长期采取“战略模糊”政策，对未来中国若对台湾发动军事攻击时的具体应对保持刻意含糊。

Although Ms. Takaichi later said that her comments did not constitute a change in Japanese policy, China’s Foreign Ministry demanded that she retract her remarks, and Chinese diplomats and commentators unleashed a stream of vitriol. Xue Jian, China’s consul general in Osaka, threatened on social media to cut off Ms. Takaichi’s “filthy head.” (He later deleted the post.)

尽管高市早苗后来表示其发言并不意味着日本的对台政策发生改变，但中国外交部要求其撤回言论，中国外交官及相关评论人士也随即对此进行猛烈抨击。中国驻大阪总领事薛剑甚至在社交媒体上威胁要砍下高市“肮脏的头颅”。（他后来删除了这则帖子。）

In its travel advisory on Friday, the Chinese embassy in Tokyo said that Japan’s leaders had made “blatantly provocative remarks regarding Taiwan, severely damaging the atmosphere of people-to-people exchanges between China and Japan and posing serious risks to the safety and security of Chinese citizens in Japan.”

在周五发布的旅行警告中，中国驻东京大使馆表示，日本领导人“公然发表涉台露骨挑衅言论，严重恶化中日人员交流氛围，给在日中国公民人身和生命安全带来重大风险”。

In response, Minoru Kihara, a top Japanese cabinet official, said on Saturday that Japan had urged China to take “appropriate measures,” Japanese news media outlets reported. He did not elaborate.

据日本媒体报道，日本内阁官房长官木原稔周六表示，日方已敦促中方采取“适当措施”，但他并未详细说明。

This is not the first time China has leveraged its outbound tourists and students during diplomatic and trade disputes. In April, as the trade war between the Washington and Beijing escalated, China’s culture and tourism ministry warned travelers to “fully assess the risks” of visiting the United States in light of deteriorating economic and trade relations. Separately, it warned students traveling to the United States to be careful.

中国此前也曾在外交或贸易争端中利用出境游客和留学生施加压力。今年4月，在华盛顿与北京的贸易战升级之际，中国文化和旅游部曾以中美经贸关系恶化为由，警告游客应“充分评估”赴美旅行的风险。该部门还提醒赴美留学生注意安全。

In 2020, China issued a starker advisory warning citizens against visiting Australia because of what it described as an increase of racism because of the coronavirus pandemic. The warnings were issued at a time when Australia was leading calls for an investigation into the origins of the coronavirus pandemic, straining relations between the two countries.

2020年，中国发布了措辞更为严厉的旅行警告，建议公民不要前往澳大利亚，理由是新冠疫情导致澳大利亚种族主义抬头。当时，澳大利亚正带头呼吁对新冠病毒的起源展开调查，导致两国关系持续紧张。

In 2017, as relations between South Korea and China deteriorated over South Korea’s decision to deploy an advanced U.S. antimissile system on its soil, China banned the sale of group tours to the country. A report by a South Korean research institute estimated that the country lost about $6.5 billion in revenue from about 3.3 million Chinese tourists over a five month period that year.

2017年，因韩国部署美国“萨德”反导系统导致中韩关系恶化，中国禁止旅行社销售赴韩团体游产品。一家韩国研究机构曾估算，韩国当年在五个月内因减少约330万中国游客损失约65亿美元旅游收入。