With the tariffs that President Trump unveiled on Wednesday, he is not just closing America’s front door to Chinese exports — he is slamming the back doors shut as well.

特朗普总统上周三公布的关税措施不仅关闭了中国出口产品进入美国的前门，也重重关上了后门。

He has now piled tariffs totaling 54 percent on goods coming straight from China, on top of tariffs of up to 25 percent that he imposed on many imports from China during his first term. More significantly, his latest actions attempt to cut off a series of alternative routes for Chinese goods to reach American store shelves and households.

他在第一任期内对许多来自中国的进口商品征收了最高25%的关税，现在又在此基础上，对直接来自中国的商品征收累计高达54%的关税。更重要的是，他的最新举措试图切断中国商品进入美国商店货架和家庭的一系列替代途径。

Since Mr. Trump began imposing tariffs on goods from China seven years ago, many Chinese companies have poured billions of dollars into building industrial parks in countries like Vietnam, Cambodia, Thailand, Malaysia and Mexico. In turn, these facilities have been importing components from China, assembling them into finished goods, and shipping them to the United States.

自从特朗普七年前开始对来自中国的商品征收关税以来，许多中国公司投入数十亿美元，在越南、柬埔寨、泰国、马来西亚和墨西哥等国建设工业园区。反过来，这些工厂一直从中国进口零部件，将它们组装为成品，然后再运往美国。

But Mr. Trump hit Mexico with extra tariffs earlier this year, and this week announced tariffs of as much as 49 percent on China’s partner countries in Southeast Asia as well.

但特朗普今年早些时候对墨西哥征收了额外关税，并于本周宣布对中国在东南亚的伙伴国家也征收高达49%的关税。

“It’s a targeted effort to seal back doors for Chinese access to the U.S. market,” said Dan Wang, a China director in the Singapore office of the Eurasia Group, a consulting firm. “The result is permanently higher import costs from China, whether direct or through third countries.”

“这是有针对性地封堵中国进入美国市场的后门，”咨询公司欧亚集团新加坡办事处的中国主管王丹（音）说。“其结果是，无论是直接进口还是通过第三国进口，来自中国的进口成本将永久性提高。”

Mr. Trump also announced on Wednesday that starting on May 2, the United States would begin collecting tariffs on the more than $60 billion a year in so-called de minimis imports from China that are exempt from tariffs now because each shipment is worth less than $800. That move will add steep taxes to the cost of packages ordered through services like Shein and Temu.

周三，特朗普还宣布，从5月2日开始，美国将开始对每年从中国进口的价值超过600亿美元的所谓“小额豁免”商品征收关税，此类商品每个包裹价值不到800美元，目前被免征关税。此举将导致通过Shein和Temu等平台订购包裹的成本额外背负高额税收。

江苏淮安一家工厂的毛巾生产线。

Mr. Trump’s tariffs are so steep on transshipment countries like Vietnam and Cambodia that they might prompt companies to reconsider China, businesspeople and analysts said. While countries in Southeast Asia offer lower wages than China, savings on labor costs there are often offset by much higher costs for materials like steel and plastic and for components like electronics, almost all of which are imported from China.

商界人士和分析人士表示，特朗普对越南和柬埔寨等转运国征收的关税过高，可能会促使企业重新考虑中国。虽然东南亚国家的工资水平低于中国，但当地劳动力成本往往会被钢铁、塑料等材料以及电子元器件等方面高得多的成本所抵消，而这些材料几乎都从中国进口。

China also benefits from many of the world’s most automated ports, new airports and an extensive network of smooth highways up to 12 lanes wide. Alternative sourcing countries in Southeast Asia have overburdened ports, crowded airports and potholed roads, all of which can lead to long, costly delays in shipments and quality problems.

中国还受益于许多世界上自动化程度最高的港口、新机场和最宽可达12车道的高速公路网络。东南亚其他采购国的港口负担过重，机场拥挤不堪，道路坑洼不平，这一切都可能导致漫长而昂贵的发货延误和质量问题。

“If no nation can escape from tariffs, I’m wondering if global supply chains will gravitate back to China, where the economics of manufacturing are too attractive,” said Han Shen Lin, China country director for the Asia Group, a consulting firm.

咨询公司亚洲集团中国区主管林汉昇说，“如果没有一个国家可以逃避关税，我在想全球供应链是否会被吸引回中国，因为中国的制造业经济太有吸引力了。”

Mr. Trump announced extra tariffs on Wednesday of 49 percent on Cambodia, 46 percent on Vietnam, 37 percent on Thailand and 24 percent on Malaysia.

特朗普周三宣布对柬埔寨、越南、泰国和马来西亚分别加征49%、46%、37%和24%的关税。

The exception among so-called backdoor countries is Mexico, to which Mr. Trump is giving special treatment, with no extra tariffs imposed on Wednesday.

在所谓的后门国家中，墨西哥是个例外，特朗普给予了它特殊待遇，周三没有对其征收额外关税。

Mexico now buys $11 worth of goods from China for every $1 that it sells to China. Such a trade imbalance would cause worries in many countries about job losses. But soaring imports from China have not triggered such worries in Mexico because most of the extra goods are being assembled at industrial parks in northern Mexico for re-export to the United States.

现在，墨西哥每向中国出口一美元，就从中国购买价值11美元的商品。在许多国家，这样的贸易不平衡会引起对失业的担忧。但在墨西哥，从中国进口的飙升并没有引发这种担忧，因为大部分额外的商品都是在墨西哥北部的工业园区组装，然后再出口到美国。

墨西哥萨尔蒂约的一家塑料制造厂。墨西哥从中国进口的大部分商品都在各工业园区完成组装，然后再出口到美国。

Mr. Trump conspicuously did not place further tariffs on Thursday on goods from Mexico. He had imposed 25 percent tariffs earlier this year on imports from Mexico, but then rescinded them for goods that mostly have components made in North America.

引人注目的是，特朗普周四没有对来自墨西哥的商品征收进一步的关税。今年早些时候，他曾对从墨西哥进口的商品征收25%的关税，但随后又取消了对大部分零部件在北美制造的商品的关税。

The net result of this initial imposition and partial removal has been that the United States now imposes 25 percent tariffs mainly on products that arrive from Mexico with a high share of Chinese content.

最初征收关税和部分取消关税的最终结果是，美国现在主要对从墨西哥进口的中国成分比例较高的产品征收25%的关税。

The United States and Mexico have been conducting talks on whether Mexico might soon raise its tariffs on all countries with which it does not have free trade agreements, said two people familiar with the talks who are not authorized to comment on them. That approach would comply with World Trade Organization rules, which Mexico is still following even as the Trump administration does not.

两名了解相关谈判情况但未获授权对此发表评论的人士称，美国和墨西哥一直在进行谈判，讨论墨西哥是否可能很快对所有与墨西哥没有自由贸易协定的国家提高关税。这种做法符合世界贸易组织的规则，墨西哥仍在遵守这些规则，即使特朗普政府并不遵守。

Mexico has free trade agreements with about 50 countries, but not with China, India or Brazil.

墨西哥与大约50个国家签订了自由贸易协定，但其中不包括中国、印度和巴西。

If Mexico raises tariffs on countries with which it does not have free trade agreements, but not with the United States and other countries with which it does have such pacts, the effect would be to tie Mexico’s economy more closely to the United States. Tariffs would keep out goods transshipped from China, but the duty-free handling that began with the North American Free Trade Agreement three decades ago would be preserved.

如果墨西哥对未与其签订自由贸易协定的国家提高关税，而不对与其签订了此类协定的美国和其他国家提高关税，其效果将是使墨西哥的经济与美国联系得更紧密。关税将阻止从中国转口的商品进入，但30年前《北美自由贸易协定》开始的免税待遇将得以保留。