Copper tariffs, with a twist

Washington's new tariffs on imported refined and semi-finished copper take effect on 1 August, and their structure surprised the market. Raw unrefined copper ores and copper cathodes are exempt. Fabricated wire, copper pipe and alloy rods face punitive duties.

From investigation to proclamation

The tariffs grew out of a national-security investigation under Section 232 of the Trade Expansion Act, opened in February, the same legal route used for steel, aluminium and cars. In early July the president said copper would face a 50 per cent duty, and the market assumed that would include cathodes, the refined plates that are the standard traded form of the metal. For months traders had shipped cathodes into American warehouses ahead of the expected levy, pushing New York prices to a wide premium over London. When the final proclamation exempted cathodes, that premium collapsed, and New York copper futures suffered one of the sharpest one-day falls on record.

A gap traders can use

The split was meant to encourage copper smelting at home while keeping raw material flowing for the energy transition. What it produced first was a large arbitrage across the world's metals exchanges. Traders began shipping raw copper into American ports for processing. Domestic fabricators went hunting for loopholes in customs classifications, relabelling finished tubing as semi-processed cathode to dodge the duties.

The incentive is easy to see. When one form of a metal enters free and a slightly more processed form pays a 50 per cent duty, the value of doing the last stage of processing inside the border jumps overnight. Every customs heading on the boundary becomes worth arguing over, and customs brokers become as important to margins as metallurgists. Enforcement falls to Customs and Border Protection, which must decide product by product where cathode ends and semi-finished copper begins. Every ruling it issues will create a new boundary for importers to test, and each test takes months to resolve.

A thin domestic base

The policy's industrial logic runs into a physical constraint. America has only two primary copper smelters in operation, in Utah and Arizona, and building a new one takes years of permitting and billions of dollars of capital. Mining is slower still. The country imports a large share of the refined metal it uses, mainly from Chile, Canada and Peru, and the exemption for cathodes is a tacit admission that domestic output cannot fill the gap. What the tariff can do quickly is protect the rod, wire and tube mills that turn cathode into finished products.

Dearer wire, dearer projects

Makers of electrical equipment and renewable-energy contractors saw the cost of their projects jump as soon as finished copper parts were taxed. Nothing else does copper's job in charging networks for electric vehicles, high-voltage transmission lines or the power systems of AI data centres.

The effect runs through contracts. A utility building a substation or a developer wiring a data centre usually buys cable, busbars and transformers from suppliers who import some of their components. Where contracts allow, the extra cost is passed on to the client; where prices were fixed before the tariff, it comes out of the contractor's margin. Utilities recover their costs from ratepayers through regulated tariffs, so part of the bill will eventually show up in electricity prices. Shortages of large transformers were already delaying grid projects before this year.

Demand is rising at the worst moment for a supply squeeze. An electric car contains several times as much copper as a petrol one, grid operators need more cable to connect new wind and solar farms, and each new data centre needs heavy wiring and switchgear. The tariff lands on precisely the goods whose use the country is trying to expand, so it raises the cost of every megawatt of new capacity rather than trimming a marginal use of the metal.

Lessons from steel

The closest precedent is steel. The safeguard tariffs imposed in 2002 were withdrawn in December 2003 after the World Trade Organisation ruled against them, and studies of that episode found that steel-using industries lost more jobs than steel producers gained. The 2018 steel and aluminium tariffs produced a similar pattern: domestic mills raised prices, and manufacturers that bought their metal paid more. Copper looks set to repeat the pattern, with the burden landing on the electrical industries the administration also says it wants to expand.

Winners, losers and the case against

The winners are domestic rod and wire mills, which now enjoy tariff-free raw material and a protected market for their output, and traders nimble enough to route metal through the gap. The losers are importers of fabricated products, equipment makers and, in the end, power users. Foreign fabricators in Canada, Mexico and Asia lose American orders unless they move the last stage of processing across the border.

The fairest case for the design is that it is less damaging than the alternative. Taxing cathodes as well would have raised costs across the entire domestic industry, including the mills the policy aims to help. A tariff on finished goods alone at least keeps raw metal cheap for American processors. That is true, and it explains the relief in the futures market. It does not change the fact that the users of finished copper, who are far more numerous than its processors, bear the cost.

What would change the call is a decision to extend the tariff to cathodes later, which the proclamation leaves open, or exclusions for specific products used in grid and power projects. Watch the premium of New York prices over London, which shows how the market judges that risk, and import data on semi-finished products over the next few months.

Trying to manage copper processing through tariff codes has raised the cost of clean-energy hardware in America and handed commodity traders an easy arbitrage, and both effects will probably last as long as the classifications do. Expect utilities and data-centre builders to report higher equipment costs within a few quarters, and expect the first customs disputes over copper classifications before the year is out.