Minerals have defined key periods in technological development for much of warfare’s history. The Stone Age featured mineral-tipped spears and arrows; the Bronze Age included swords and shields of bronze, a metal alloy of copper and tin; and in the Iron Age, iron replaced bronze in many weapons, making them both lighter and cheaper. Since then, minerals have remained formative in changing human history—and warfighting. The cheap, mass production of iron was central to the First Industrial Revolution, while steel, an alloy of iron and carbon, was vital to the Second Industrial Revolution. Both periods contributed to the industrialization of war.

Today, minerals still undergird warfighting technology, including defense platforms and munitions. Virtually every US military system requires mineral components, from steel and titanium to graphite composites and cadmium alloys. Global defense spending shows that military demand is increasing for these platforms, munitions, and thus minerals. Like previous junctions in human history, the current period will be defined by minerals and the warfighting technology that they enable.

US military demand for minerals is expected to grow against a backdrop of rising US-China competition and the prospect of a US-China war in Asia. However, US mineral supply chains presently rely heavily on China, which can restrict supply to the United States, and Asian countries like Japan and South Korea, whose sea lines of communication to the United States would be disrupted in a US-China conflict. Importantly, the Russia-Ukraine war has shown that attrition rates for this war materiel in a conflict often outpace replenishment rates. In short, future US access to adequate supplies of warfighting-enabling minerals is endangered. To reduce this mineral vulnerability, the US government could stockpile more minerals, source these minerals from domestic mines and refineries, and provide grants to existing refineries to process byproducts that are currently not processed.

Metal Machines of War

Today, US forces rely heavily on platforms and munitions produced with minerals. Since China is the “pacing challenge” and will be militarily prepared to invade Taiwan in 2027, the US military is prioritizing the maritime and air forces that would play central roles in a conflict in the Indo-Pacific region, as well as long-range precision fires for land forces.

In the sea domain, the US Navy wants to grow its force to over five hundred ships. In its FY 2024 budget request, the Navy seeks to procure nine battle force ships, including one ballistic missile submarine, two fast-attack submarine, two destroyers, and two frigates. The hulls of these are made of high-strength, alloyed steel. For example, the hulls of most modern US submarines use high-yield (HY)-100 steel, which contains metals like nickel, chromium, molybdenum, and manganese. Navy armaments are also metal-intensive. For instance, the Tomahawk cruise missile has an aluminum airframe, and the Mark 48 torpedo has an aluminum fuel tank.

In the air domain, the US Air Force seeks to procure nearly one hundred aircraft, including forty-eight F-35 fighter jets, according to its FY 2024 budget request. Many military airframes use titanium. To illustrate, nearly 20 percent of the F-35 fighter jet’s weight is titanium. Air Force platforms are also equipped with armaments containing metal. For example, Joint Air-to-Surface Standoff Missiles—which can be launched by both strategic bombers and tactical fighters—have concrete-piercing casings made of tungsten steel. The air-launched, anti-ship Harpoon missile (Standoff Land Attack Missile–Expanded Response) has cadmium-plated and nickel-plated electrical connectors and structural fasteners, as well as chromium-coated parts.

For land forces in the Indo-Pacific, the US Army is focusing on bolstering long-range precision fires, which include artillery, rockets, and missiles. These munitions use metal. For instance, the M30A1 rocket explodes with 182,000 tungsten ball bearings, targeting personnel and light-skinned vehicles. Artillery shells are often made of a high-fragmentation steel alloy such as manganese. The platforms that launch these munitions also contain metal. The Patriot surface-to-air missile system launches missiles from reinforced aluminum canisters, and the Army’s family of medium tactical vehicles, which often hold long-range fire munitions, has frames of high-strength steel. In sum, the US military depends greatly on mineral-intensive platforms and munitions.

Breaking Foreign Dependence

But, for many minerals, the United States relies heavily on foreign imports, including from China, and these supply chains are vulnerable to disruption. For example, the United States is 100 percent reliant on foreign imports for domestic consumption of gallium and graphite, although Syrah Resources expects to begin producing natural graphite-based anode materials this December. The United States is also mainly reliant on foreign imports for its consumption of germanium. China, however, is the world’s largest producer of gallium, germanium, and natural and synthetic graphite, and it is the largest import source for the United States for these materials. Notably, China recently imposed export restrictions on gallium, germanium, and graphite, requiring licenses to export these goods and disrupting supplies to the United States. China could impose similar restrictions on other minerals.

Resource-rich countries from where the United States could alternatively source minerals are also adopting trade restrictions to require more downstream processing. These countries seek the expanded economic benefits of value-added processing, such as job creation and capital investments. Indonesia, the world’s largest nickel producer due to Chinese investments, banned the export of nickel ore in 2020. Eyeing Indonesia’s model, the Philippines, the world’s second-largest producer of mined nickel, is considering banning or taxing the export of its nickel ore. Zimbabwe, which has Africa’s largest lithium reserves and some of the world’s largest hard rock lithium reserves, banned the export of unprocessed lithium in 2022. Ghana and Namibia have also banned the export of unprocessed minerals. The United States could alternatively source minerals from Canada and Australia, but their resources are often more expensive to mine given their lower grades and deeper depths. In short, US supply chains for minerals—and thus military platforms and munitions—are vulnerable.

Such risks to US mineral supply chains, however, are neither new nor unique. In 1939, Congress established the Strategic and Critical Materials Stockpiling Act of 1939, creating the National Defense Stockpile, which is managed by the Department of Defense’s Defense Logistics Agency. The purpose of the stockpile is to decrease and prevent US reliance on risky and costly sources of supply, as well as “encourage the conservation and development of sources of such materials within the United States.” However, the size of the stockpile has fallen tremendously, with the its value in 2022 approximately 2.5 percent of its value in 1952, corrected for inflation.

To increase domestic production of critical minerals, the Department of Defense primarily relies on the Manufacturing Capability Expansion and Investment Prioritization (MCEIP) office, which contains the Industrial Base Analysis and Sustainment program and the Defense Production Act Title III program. The MCEIP office’s largest investment area is strategic and critical materials, and the office has announced eight awards related to mineral supply chains already in 2023, compared to just five awards total from 2020 through 2022. In September 2023 alone, the MCEIP announced awards to a lithium mine, nickel project, and rare earth magnet manufacturing facility. Thus, the Department of Defense is increasingly focused on growing domestic production of critical minerals.

Given the recency of the awards and the long lead times to develop mineral projects, the impact of these efforts remains to be seen. However, the Department of Defense can take additional actions to strengthen domestic mineral supply chains. To hedge against supply risk, it could request additional funds from Congress to increase the National Defense Stockpile. To catalyze investment in domestic mineral projects and support existing domestic mineral producers, it could increase the National Defense Stockpile by sourcing domestically mined and refined minerals—which has precedent. From 1946 to 1961, the US government acquired about 60 percent of all domestic cobalt production, and it paid a premium price for some of this material. Growing the National Defense Stockpile by sourcing domestically mined and refined minerals would both protect against supply disruptions and support the domestic mineral industry.

To increase domestic production of refined critical minerals, the Department of Defense could provide financial incentives to existing refineries for processing byproducts contained in ore. For example, gallium is contained in bauxite and zinc ores, but given low demand volume and volatile gallium prices, most alumina smelters that process these ores forgo extracting gallium. The Department of Defense could provide grants to cover the capital expenditures necessary to extract gallium. Moreover, in the event of a US-China war, the department could use the Defense Production Act to require domestic alumina smelters to extract gallium, as China already does. Therefore, the Department of Defense has additional options for strengthening domestic mineral supply chains.

Minerals undergird warfighting technology, just like they have during past ages. However, as tensions—and the prospect of war—rise with China, the US military is vulnerable, relying heavily on foreign sources of minerals for its defense platforms and munitions. In a protracted, high-intensity conflict with China, the US defense industrial base may lack sufficient minerals to support the war effort. The US military will remain vulnerable—and may risk defeat in a potential US-China conflict—if the Department of Defense fails to bolster its stockpile and grow domestic mineral production. Like previous junctions in human history, the current period of US-China competition will be defined by minerals and the warfighting technology that they enable.

Macdonald Amoah is a researcher at the Payne Institute for Public Policy at the Colorado School of Mines.

Gregory Wischer is principal at Dei Gratia Minerals, a critical minerals consultancy.

Juliet Akamboe is a critical minerals demand researcher at the Colorado School of Mines.

Morgan Bazilian is director of the Payne Institute and Professor of Public Policy at the Colorado School of Mines.

The views expressed are those of the authors and do not reflect the official position of the United States Military Academy, Department of the Army, or Department of Defense.

Image credit: Airman 1st Class Karissa Dick, US Air Force