US munitions stockpiles significantly depleted after 38-day campaign against Iran, raising concerns about readiness in other theatres

Introduction

The United States military has expended substantial quantities of advanced munitions during its 38-day campaign against Iran, which commenced on February 28 and was followed by a ceasefire. Internal Pentagon estimates and congressional sources indicate that inventories of several critical missile systems have been reduced to levels that may affect the military''s ability to respond to potential conflicts in other regions, particularly the Indo-Pacific.

Main Body

According to internal Defense Department estimates and congressional officials cited in multiple reports, the US used approximately 1,100 Joint Air-to-Surface Standoff Missile-Extended Range (JASSM-ER) stealth cruise missiles, each costing roughly $1.1 million, leaving an estimated 1,500 remaining. More than 1,000 Tomahawk cruise missiles, priced at about $3.6 million each, were also fired—approximately ten times the annual procurement rate. The Pentagon deployed over 1,200 Patriot interceptor missiles, each exceeding $4 million, and more than 1,000 Precision Strike and ATACMS ground-based missiles. A study by the Center for Strategic and International Studies (CSIS) estimated that the Tomahawk stockpile now stands at around 3,000 missiles, a level considered insufficient for a major conflict in the Western Pacific. The strain on air-defence systems is particularly acute: the US produced roughly 600 Patriot interceptors in all of 2025, yet used more than double that number in the campaign. The overall financial cost of the conflict has been estimated by two independent groups—the American Enterprise Institute and CSIS—at between $28 billion and $35 billion, with $5.6 billion consumed in the first 48 hours alone. The depletion of munitions has forced the Pentagon to redirect weapons and personnel from other regional commands. In Europe, the loss of surveillance and attack drones has been described as a serious problem, affecting NATO''s eastern flank and the ability to deter Russian aggression. In Asia, the USS Abraham Lincoln carrier strike group was redeployed from the South China Sea to the Middle East before the conflict began, and two Marine Expeditionary Units totaling approximately 4,400 personnel were moved from the Pacific. For the first time, interceptor missiles from the Terminal High Altitude Area Defence (THAAD) system stationed in South Korea—originally deployed to counter North Korean missile threats—have been redirected to the Middle East. Admiral Samuel Paparo, head of US Indo-Pacific Command, acknowledged during a Senate hearing that “there are finite limits to the magazine” but stated that ongoing operations have not imposed a real cost on deterrence against China. White House Press Secretary Karoline Leavitt rejected claims of shortfalls, stating that “the entire premise of this story is false” and that the US military remains “fully loaded with more than enough weapons and munitions.” Pentagon spokesperson Sean Parnell declined to comment on specific theatre requirements, citing operational security. However, analysts and some lawmakers have expressed concern about the time required to reconstitute stockpiles. Senator Jack Reed (D-RI) noted that “at current production rates, reconstituting what we have expended could take years.” Retired Marine Corps Colonel Mark Cancian of CSIS observed that “some critical ground-attack and missile-defence munitions were short before the war and are even shorter now.” A CSIS report warned that high expenditure rates have created “a window of increased vulnerability in the western Pacific.” The Pentagon has not yet begun expanded production, despite having secured seven-year agreements in January with major defence contractors such as Lockheed Martin to quadruple output of precision-guided munitions and THAAD interceptors. Officials stated that no expanded production has commenced because the funding—reportedly a $200 billion supplemental appropriations request—is still awaiting congressional approval. Separately, the conflict has also incurred unexpected costs from destroyed aircraft, including two MC-130 cargo planes and three MH-6 helicopters, estimated at about $275 million. Broader economic effects include a rapid increase in US gasoline prices as the conflict threatened the Strait of Hormuz, through which approximately 20% of the world''s daily oil supply passes.

Conclusion

The US military campaign against Iran has resulted in a significant drawdown of advanced munitions, particularly long-range strike missiles and air-defence interceptors. While the White House maintains that stockpiles remain sufficient for all operational requirements, independent analysts and internal estimates indicate that rebuilding inventories to pre-war levels could take years, potentially creating a period of reduced readiness in other strategic theatres, especially the Indo-Pacific. The Pentagon is awaiting congressional funding to initiate expanded production, and the duration of any future conflict or renewed operations against Iran would further affect the balance between immediate needs and long-term deterrence.

Vocabulary Learning

deterrence
The use of threat or military capability to discourage an adversary from taking an unwanted action.威懾;威懾力
Example:Admiral Paparo stated that ongoing operations have not imposed a real cost on deterrence against China.
drawdown
A reduction or decrease in the quantity of something, typically military forces or supplies.減少;縮減(尤指軍事力量或物資)
Example:The US military campaign against Iran has resulted in a significant drawdown of advanced munitions.
magazine
A storage place for ammunition or explosives; also used metaphorically to refer to a stockpile of munitions.彈藥庫;軍火庫(亦比喻為彈藥儲備)
Example:Admiral Samuel Paparo acknowledged that 'there are finite limits to the magazine.'
reconstitute
To restore something to its original state or condition, especially after depletion or damage.重建;恢復原狀(尤指在耗盡或損壞後)
Example:Senator Jack Reed noted that 'at current production rates, reconstituting what we have expended could take years.'
theatre
A region or area in which military operations are conducted.戰區;軍事行動區域
Example:The depletion of munitions may affect the military's ability to respond to potential conflicts in other theatres, particularly the Indo-Pacific.

Sentence Learning

According to internal Defense Department estimates and congressional officials cited in multiple reports, the US used approximately 1,100 Joint Air-to-Surface Standoff Missile-Extended Range (JASSM-ER) stealth cruise missiles, each costing roughly $1.1 million, leaving an estimated 1,500 remaining.
Structural Analysis in English This sentence begins with a prepositional phrase 'According to... reports' containing a reduced relative clause 'cited in multiple reports' modifying 'officials'. The main clause is 'the US used approximately 1,100 ... missiles'. This is followed by an absolute participial phrase 'each costing roughly $1.1 million' (nominative absolute) and a resultative participial phrase 'leaving an estimated 1,500 remaining'. The sentence exhibits high lexical density with technical terms and numbers.Structural Analysis in Standard Written Traditional Chinese (Hong Kong) 本句以介詞短語「根據...報告」開首,當中包含簡化關係從句「被多份報告引述的」修飾「官員」。主句為「美國使用了約1,100枚...導彈」。其後接獨立分詞短語「每枚造價約110萬美元」(主格獨立結構)及結果分詞短語「留下約1,500枚剩餘」。句子展現高詞彙密度,包含專業術語及數字。
For the first time, interceptor missiles from the Terminal High Altitude Area Defence (THAAD) system stationed in South Korea—originally deployed to counter North Korean missile threats—have been redirected to the Middle East.
Structural Analysis in English The sentence starts with a fronted adverbial 'For the first time'. The subject is 'interceptor missiles from the THAAD system', with a reduced relative clause 'stationed in South Korea' modifying 'system'. A parenthetical insertion set off by em dashes '—originally deployed to counter North Korean missile threats—' provides additional information using a reduced relative clause. The main verb is 'have been redirected' (present perfect passive). This sentence demonstrates the use of parenthetical elements and reduced clauses for conciseness.Structural Analysis in Standard Written Traditional Chinese (Hong Kong) 句首為前置狀語「首次」。主語為「來自THAAD系統的攔截導彈」,帶有簡化關係從句「部署在南韓的」修飾「系統」。破折號插入的補充說明「——最初為應對北韓導彈威脅而部署——」使用簡化關係從句。主要動詞為「已被重新部署」(現在完成被動式)。本句展示插入語及簡化從句的運用,以達簡潔效果。
The Pentagon has not yet begun expanded production, despite having secured seven-year agreements in January with major defence contractors such as Lockheed Martin to quadruple output of precision-guided munitions and THAAD interceptors.
Structural Analysis in English The main clause is 'The Pentagon has not yet begun expanded production'. This is followed by a concessive participial phrase 'despite having secured seven-year agreements...', which itself contains an infinitive phrase 'to quadruple output...' indicating purpose. The phrase 'such as Lockheed Martin' is an example. The sentence uses a perfect participial phrase to express an action completed before the main clause, and an infinitive of purpose, demonstrating complex temporal and logical relationships.Structural Analysis in Standard Written Traditional Chinese (Hong Kong) 主句為「五角大樓尚未開始擴大生產」。其後接讓步分詞短語「儘管已簽訂七年協議...」,該短語內含不定式短語「將產量提高四倍...」表示目的。短語「如洛克希德·馬丁」為舉例。句子使用完成分詞短語表達在主句之前完成的動作,以及目的不定式,展示複雜的時間與邏輯關係。
Broader economic effects include a rapid increase in US gasoline prices as the conflict threatened the Strait of Hormuz, through which approximately 20% of the world's daily oil supply passes.
Structural Analysis in English The main clause is 'Broader economic effects include a rapid increase in US gasoline prices'. This is followed by a causal adverbial clause 'as the conflict threatened the Strait of Hormuz'. Within that clause, there is a non-restrictive relative clause 'through which approximately 20% of the world's daily oil supply passes', modifying 'Strait of Hormuz'. The relative clause uses a preposition 'through' + 'which', and the verb 'passes' is in simple present. The sentence combines causal and relative subordination, with high lexical density.Structural Analysis in Standard Written Traditional Chinese (Hong Kong) 主句為「更廣泛的經濟影響包括美國汽油價格迅速上漲」。其後接因果狀語從句「因為衝突威脅霍爾木茲海峽」。該從句內含非限制性關係從句「全球每日約20%石油供應經此通過」,修飾「霍爾木茲海峽」。關係從句使用介詞「經」+「which」,動詞「通過」為一般現在時。句子結合因果及關係從屬,詞彙密度高。
While the White House maintains that stockpiles remain sufficient for all operational requirements, independent analysts and internal estimates indicate that rebuilding inventories to pre-war levels could take years, potentially creating a period of reduced readiness in other strategic theatres, especially the Indo-Pacific.
Structural Analysis in English This is a complex sentence with a concessive clause introduced by 'While'. The concessive clause contains a that-clause: 'the White House maintains that stockpiles remain sufficient...'. The main clause is 'independent analysts and internal estimates indicate that rebuilding inventories... could take years'. This main clause is followed by a participial phrase 'potentially creating a period of reduced readiness...', which itself includes an appositive 'especially the Indo-Pacific'. The sentence demonstrates concessive subordination, multiple that-clauses, and a resultative participial phrase, showcasing advanced syntactic layering.Structural Analysis in Standard Written Traditional Chinese (Hong Kong) 本句為複雜句,以「雖然」引導讓步從句。讓步從句包含that從句:「白宮堅稱庫存仍足夠...」。主句為「獨立分析師和內部估計表明,重建庫存...可能需要數年」。主句後接分詞短語「可能造成一段戰備減弱時期...」,該短語內含同位語「尤其是印太地區」。句子展示讓步從屬、多個that從句及結果分詞短語,體現高級句法層次。