美國將透過第 301 條款，以其所稱由政府干預所驅動的「結構性過剩產能」為由，擴大與多個國家的貿易衝突。根據 Bloomberg，中國是其中的目標：

The US is set to impose a 7.5% tariff on Chinese goods over allegations of excess manufacturing capacity before a planned summit between Xi Jinping and Donald Trump next month, according to people familiar with the matter. The move would restore Trump’s second-term duties on China to around 20%, a level Beijing has previously said is consistent with its trade truce with Washington. Those come on top of other levies imposed during Trump’s first term and extended during the Biden administration.

The US is set to impose a 7.5% tariff on Chinese goods over allegations of excess manufacturing capacity before a planned summit between Xi Jinping and Donald Trump next month, according to people familiar with the matter.

The move would restore Trump’s second-term duties on China to around 20%, a level Beijing has previously said is consistent with its trade truce with Washington. Those come on top of other levies imposed during Trump’s first term and extended during the Biden administration.

這一發展早已在 Brookings 於 3 月發表的 “After IEEPA” 一文中有所預告。

3 月 11 日宣布的 16 項調查聚焦於政府所稱的「結構性過剩產能」。USTR 指稱，包括中國、歐盟、日本、墨西哥、印度、瑞士、挪威及其他國家在內的若干經濟體，維持補貼、國家融資與產業規劃等政府政策，即使市場條件不支持，工廠仍得以持續生產。

3 月 11 日宣布的 16 項調查聚焦於政府所稱的「結構性過剩產能」。USTR 指稱，包括中國、歐盟、日本、墨西哥、印度、瑞士、挪威及其他國家在內的若干經濟體，維持補貼、國家融資與產業規劃等政府政策，即使市場條件不支持，工廠仍得以持續生產。

作者不記得自己在大學或研究所的國際貿易課程中學過「過剩產能」這個術語。查閱標準教科書後，也沒有找到相關用法。

這並不表示這個詞在經濟學中毫無位置。在壟斷性競爭模型中，過剩產能會明確出現，但這類討論原本是在完全國內、封閉經濟的背景下提出的。

如果「過剩產能」只是指一個國家沒有生產到其能達到的最大程度，那麼問題就在於門檻設在哪裡。從第 301 條款調查的 Federal Register 公告來看，答案似乎是 80%。

根據 World Bank 數據，2024 年全球製造業產出達到 16.6 兆美元，高於 2023 年的 16.4 兆美元。儘管如此，美國政府估計，全球製造業產能利用率仍介於 75.0% 至 75.9% 之間，低於許多產業約 80% 的健康利用率。2 這顯示，就製造品而言，雖然全球生產持續擴張，但潛在的全球供給仍高於潛在的全球需求。

根據 World Bank 數據，2024 年全球製造業產出達到 16.6 兆美元，高於 2023 年的 16.4 兆美元。儘管如此，美國政府估計，全球製造業產能利用率仍介於 75.0% 至 75.9% 之間，低於許多產業約 80% 的健康利用率。2 這顯示，就製造品而言，雖然全球生產持續擴張，但潛在的全球供給仍高於潛在的全球需求。

80% 這個基準看來是借自鋼鐵相關的過剩產能文獻。

接下來，問題從貿易理論轉向貿易法，而兩者並不總是一致，反傾銷法就是例子。USTR 似乎也在以不同於其在 2025 National Trade Estimate Report 中對過剩產能的描述方式，來界定結構性過剩產能。

正如 Global Trade Alert 所指出：

The definitional scope is measurable. In the 2025 National Trade Estimate Report, published a year earlier, USTR discussed overcapacity for two economies : China (steel, aluminium, solar, electric vehicles, batteries) and Indonesia (mineral ore export bans contributing to steel overcapacity). The Section 301 announcement applies ‘structural excess capacity’ to 16 economies. USTR’s Background section defines two analytical layers: evidentiary indicators (trade surpluses, low capacity utilisation, sector overcapacity, unprofitable firms) and seven policy interventions said to cause them (production subsidies, wage suppression, state-owned enterprise activities, market access barriers, lax environmental or labour protection, subsidised lending, and currency manipulation). Across all 16 economies, the announcement documents 33 evidentiary indicators but cites only seven specific policy interventions. For ten economies, it identifies symptoms but leaves the causes subject to investigation. Three economies illustrate the breadth of the definition. Switzerland is cited for currency intervention and sterilisation of foreign exchange inflows, with no industrial overcapacity evidence and no policy interventions identified beyond currency practices. The NTE’s Switzerland chapter discusses tariffs, agricultural subsidies, sanitary measures, and data localisation; it contains no mention of overcapacity, currency manipulation, or trade surplus as a concern. Norway is cited for recycling oil revenues through its sovereign wealth fund rather than its domestic currency; its bilateral surplus with the United States is $1.9 billion. The NTE’s Norway chapter contains no reference to currency practices, sovereign wealth operations, or overcapacity. Japan runs a global goods trade deficit of roughly $36 billion but is included on the basis of its bilateral surplus and the share of unprofitable firms in its economy. Divergence from the National Trade Estimate Report The S301 and the NTE diverge significantly. A systematic review of the 2025 NTE across all 16 targeted economy chapters finds that the S301’s core categories scarcely appear in the NTE’s analytical vocabulary. Neither currency intervention, undervaluation, nor zombie firms feature as concerns anywhere in the document. ‘Overcapacity’ is confined almost entirely to the China section and one brief Indonesia reference. The divergence extends to policy causes: the NTE documents instances of USTR’s own seven policy interventions far more extensively than the S301 does. Market access barriers, for instance, are documented in the NTE for 15 of the 16 targeted economies; the S301 does not cite market access barriers as a cause of overcapacity for any of them, though some country sections describe practices (such as Indonesia’s export restrictions) that could plausibly be characterised under that heading. The NTE is a document about the causes of trade distortion. The S301, at this stage, documents indicators and leaves most causes unspecified. The definitional scope is measurable. In the 2025 National Trade Estimate Report, published a year earlier, USTR discussed overcapacity for two economies : China (steel, aluminium, solar, electric vehicles, batteries) and Indonesia (mineral ore export bans contributing to steel overcapacity). The Section 301 announcement applies ‘structural excess capacity’ to 16 economies. USTR’s Background section defines two analytical layers: evidentiary indicators (trade surpluses, low capacity utilisation, sector overcapacity, unprofitable firms) and seven policy interventions said to cause them (production subsidies, wage suppression, state-owned enterprise activities, market access barriers, lax environmental or labour protection, subsidised lending, and currency manipulation). Across all 16 economies, the announcement documents 33 evidentiary indicators but cites only seven specific policy interventions. For ten economies, it identifies symptoms but leaves the causes subject to investigation. Three economies illustrate the breadth of the definition. Switzerland is cited for currency intervention and sterilisation of foreign exchange inflows, with no industrial overcapacity evidence and no policy interventions identified beyond currency practices. The NTE’s Switzerland chapter discusses tariffs, agricultural subsidies, sanitary measures, and data localisation; it contains no mention of overcapacity, currency manipulation, or trade surplus as a concern. Norway is cited for recycling oil revenues through its sovereign wealth fund rather than its domestic currency; its bilateral surplus with the United States is $1.9 billion. The NTE’s Norway chapter contains no reference to currency practices, sovereign wealth operations, or overcapacity. Japan runs a global goods trade deficit of roughly $36 billion but is included on the basis of its bilateral surplus and the share of unprofitable firms in its economy. Divergence from the National Trade Estimate Report The S301 and the NTE diverge significantly. A systematic review of the 2025 NTE across all 16 targeted economy chapters finds that the S301’s core categories scarcely appear in the NTE’s analytical vocabulary. Neither currency intervention, undervaluation, nor zombie firms feature as concerns anywhere in the document. ‘Overcapacity’ is confined almost entirely to the China section and one brief Indonesia reference. The divergence extends to policy causes: the NTE documents instances of USTR’s own seven policy interventions far more extensively than the S301 does. Market access barriers, for instance, are documented in the NTE for 15 of the 16 targeted economies; the S301 does not cite market access barriers as a cause of overcapacity for any of them, though some country sections describe practices (such as Indonesia’s export restrictions) that could plausibly be characterised under that heading. The NTE is a document about the causes of trade distortion. The S301, at this stage, documents indicators and leaves most causes unspecified. It’s worth mentioning that there are several industries for which capacity utilitzation is below 80% and export: More discussion from Evenett, here , in the context of the US and China.