If you follow the policy debate around critical minerals, you could be forgiven for thinking Western militaries are on the brink of running out of the materials needed to build weapons.
Defence planners warn about supply chains dominated by China. Politicians talk about mineral shortages undermining national security. Headlines suggest that without urgent action, Western defence capabilities could be crippled.
There is truth in these concerns. Modern weapons systems depend on a surprisingly wide range of specialised metals. Precision missiles, drones, radars, and fighter jets rely on materials that must perform under extreme conditions—heat, vibration, radiation, and electromagnetic interference.
But there is also an important reality that often gets lost in the discussion.
Defence accounts for less than 5% of global critical mineral demand.
Even if geopolitical tensions lead to a major rearmament cycle—and defence demand doubles—military use would still represent a relatively small slice of global consumption.
The real drivers of critical mineral demand today are electric vehicles, batteries, grid infrastructure, consumer electronics and AI and its related power requirements, not missiles.
Yet wars do serve a useful purpose in the public debate: they remind us that advanced military systems ultimately depend on physical materials. Strip away the software, sensors, and algorithms, and modern weapons are still machines built from metals.
A good way to understand this dependency is through one of the most recognisable weapons ever built: the Tomahawk cruise missile.
A Missile Is Really a Flying Machine
The Tomahawk, produced by Raytheon (now part of RTX), is essentially a compact autonomous aircraft.
It weighs roughly 1.2–1.6 tonnes and can travel more than 1,600 kilometres, flying low across terrain before striking targets with remarkable precision. It achieves this through a combination of inertial navigation, GPS, terrain contour matching, and sophisticated onboard computing.
But none of that technology works without the underlying hardware.
The missile is built from several core systems, each made possible by specialised materials.
Airframe and Body
The Tomahawk’s fuselage and wings are primarily built from lightweight aluminium alloys. These alloys provide the structural strength required to survive launch forces while keeping the missile light enough for long-range flight.
The airframe also houses the missile’s electronics, fuel tanks, and guidance systems.
Wings and Control Surfaces
After launch, folding wings deploy so the missile can transition into sustained flight. Adjustable fins and control surfaces allow the missile to manoeuvre and maintain its course.
These components rely on precision actuators and electric motors, many of which use rare earth permanent magnetsmade from materials such as samarium and neodymium. These magnets provide extremely strong magnetic fields in compact spaces and can operate reliably in high-temperature environments.
Propulsion System
The Tomahawk uses two propulsion systems.
At launch, a solid rocket booster accelerates the missile away from ships or submarines.
Once airborne, a Williams International F107 turbofan engine powers sustained subsonic flight. The engine’s high-temperature components rely on specialised alloys capable of withstanding intense heat and mechanical stress.
Warhead
The missile carries a high-explosive unitary warhead or specialised penetrating variants depending on the mission. These components incorporate materials designed to withstand extreme acceleration during launch and impact.
Guidance and Electronics
Perhaps the most sophisticated part of the Tomahawk is its guidance system. This includes:
Inertial navigation systems (INS)
GPS receivers
Terrain contour matching (TERCOM)
Digital scene matching area correlator (DSMAC)
Radar altimeters
Onboard flight computers
These systems allow the missile to compare real terrain with digital maps and adjust its flight path in real time.
All of these electronics depend on high-performance materials that enable reliable power management, signal transmission, and miniaturisation.
The Hidden Minerals in Modern Weapons
Although the exact bill of materials remains classified, defence analyses suggest the Tomahawk relies on roughly 18 critical minerals across its guidance systems, propulsion components, and electronics.
Many of these materials appear in small quantities but perform functions that are extremely difficult to replace.
Rare earth elements are among the most important.
Samarium is used in samarium-cobalt magnets, which are extremely resistant to heat and demagnetisation. These magnets power actuators that control the missile’s fins and flight surfaces.
Neodymium—often combined with dysprosium and terbium—is used in neodymium-iron-boron magnets, which drive compact electric motors used in guidance systems and propulsion controls.
Then there is silver, one of the best electrical conductors known, used in wiring, circuit boards, connectors, and power systems.
Other specialised materials include tungsten, valued for its density and heat resistance, and tantalum, used in high-performance capacitors that stabilise electrical systems inside the missile.
Antimony may appear in explosive compounds and flame-retardant components.
In some cases, cobalt appears in specialised alloys used in propulsion systems or other high-stress components. But the quantities involved are extremely small—perhaps one to three kilograms per missile.
And that is where the economics of defence production become interesting.
Minerals Are a Tiny Part of the Cost
A Tomahawk missile costs roughly $2 million.
The minerals inside it—however strategically important—represent a tiny fraction of that cost.
Take cobalt as an example. A few kilograms of cobalt at current prices might cost $60–90 in raw metal value.
Even the silver inside the missile, despite its relatively large quantity, represents a small share of the overall system cost.
What matters to defence contractors is not the commodity cost of the metal. What matters is performance.
If a specific alloy or magnet material allows a missile to operate more reliably, survive higher temperatures, or maintain accuracy over long distances, it will be used regardless of cost.
The materials enable the capability. The cost of the material itself is almost irrelevant.
This makes defence procurement fundamentally different from most industrial supply chains.
Defence Is the Least Price-Sensitive Buyer
In most industries, companies constantly search for ways to reduce input costs. If a cheaper substitute material can perform the same function, manufacturers will switch.
Defence does not work that way.
Weapons systems are designed around maximum reliability and performance, not cost optimisation. If a critical material is needed to ensure a missile can strike a target with precision after flying for more than 1,500 kilometres, it will be used.
And if supply becomes scarce, defence contractors can simply pay more.
This is why the idea that mineral shortages will cripple Western defence capabilities is often overstated.
If necessary, the defence sector can outbid almost any other buyer for critical materials. Compared with the overall cost of advanced weapons systems, the raw materials involved are trivial.
Even if non-Chinese supply chains are limited, defence manufacturers can secure the volumes they need by paying a premium.
The Real Supply Chain Problem
None of this means supply chains do not matter.
They absolutely do.
China currently dominates the processing of many critical minerals, particularly rare earth elements and permanent magnets used in electronics and defence systems. In some cases, more than 90% of global refining capacity sits within Chinese supply chains.
That concentration creates strategic risk.
Recent export restrictions by China on certain rare earth elements—including samarium—have already disrupted supply chains for some defence components.
These concerns have prompted a wave of new legislation in the United States aimed at reducing dependence on Chinese materials.
Under recent provisions in the FY2026 National Defense Authorization Act, the U.S. Department of Defense is gradually banning the use of certain minerals if they are mined, refined, or processed in “covered nations,” including China.
The rules place particular emphasis on rare earth permanent magnets, which are critical for motors, guidance systems, and electronic components in missiles, aircraft, and drones.
By 2027, defence contractors will be prohibited from using Chinese-origin permanent magnets in many weapons systems.
Contractors must now trace supply chains and demonstrate the origin of critical materials used in defence platforms.
The objective is clear: create secure supply chains among allied countries.
But building those supply chains takes time.
The Bigger Picture
Despite the headlines, the defence sector is not the main driver of mineral demand.
Even during wartime, the quantities of materials used in missiles, aircraft, and other military hardware are relatively small compared with the volumes required by the civilian economy.
Electric vehicles, batteries, renewable energy systems, and electronics consume vastly larger quantities of lithium, cobalt, nickel, rare earths, copper, and other materials.
That is where the real demand growth is occurring.
In other words, defence highlights the importance of critical minerals, but it is not what drives the market.
What wars do is remind us of something more fundamental.
Modern military power—like modern civilisation itself—is ultimately built on a foundation of physical materials.
The Tomahawk missile may look like a triumph of software, electronics, and guidance technology.
But at its core, it is still a machine built from metals pulled from the ground.
And that reality—the mineral imperative—applies just as much to the battlefield as it does to the rest of the modern economy.
**This is based on declassified reports, defense industry analyses, and public discussions—detailed specs remain restricted.
During WWII, extreme measures were taken to funnel necessary materials to the military and rationing them for consumers - because it was an existential crisis.
If anything like that developed today, with the US being really threatened (if China and Russia were to join Iran, although I hope that's a very remote possibility) we would make sure the military and defense contractors got priority for needed minerals.
Excellent piece. I would add one distinction that becomes especially important in wartime: the ability to pay more is not always the same as the ability to obtain more.
Defence may be one of the least price-sensitive buyers, but once a critical-material supply chain becomes strategically contested, price can cease to be the governing constraint. Mining, separation, refining, alloy production, magnet manufacturing, qualification, certification, transport, and stockpiles all sit between the mineral in the ground and the weapon on the launcher.
You can outbid another commercial buyer. You cannot necessarily outbid an export restriction, replace a processing monopoly overnight, or instantly qualify a substitute component for a mature weapons system.
So I think the deeper vulnerability is not the cost of the mineral, but the architecture of access to it. In peacetime, money can buy priority. In a serious conflict, industrial depth and sovereign control may determine continuity.