A chip inside an American laptop has usually traveled across several borders before installation. The production chain is split into distinct stages, and each stage concentrated in a different part of the world.
Design and manufacturing separated decades ago
Building a leading-edge fabrication plant became so expensive that most companies stopped trying. They became fabless designers, selling the layout of a chip rather than the physical product.
Foundries emerged to serve them, manufacturing to order for many customers at once. That division let design firms compete on architecture without carrying the capital burden of a plant.
The split is why a chip can be designed in one country, fabricated in another, and sold under a brand headquartered somewhere else entirely without anything unusual having occurred.
Equipment and materials come from elsewhere again
The machines that pattern silicon at the smallest dimensions are made by a very small number of suppliers, concentrated in a handful of countries and effectively irreplaceable in the short term.
Specialty chemicals, photoresists and ultra-pure silicon wafers form their own concentrated supply lines, with certain grades produced by only a few firms worldwide.
Each of these inputs crosses a border before fabrication even begins, which means the finished wafer already embeds material from several countries by the time it exists.
Packaging and testing happen in another place
A finished wafer is cut into individual dies, which must then be mounted, connected and sealed into a package that can be soldered onto a board.
This work is more labor-intensive and less capital-intensive than fabrication, so it settled in different countries from the ones hosting the most advanced foundries.
Testing follows, and failed units are discarded at this stage. Wafers therefore ship out of the fabrication country and the packaged chips ship onward again to assembly.
Origin becomes genuinely ambiguous
Customs must assign one country of origin to a product whose value was created in several. The answer depends on where substantial transformation is judged to occur.
Reasonable rules can point to different places. Fabrication creates the circuitry, but packaging produces the article that is actually sold as a chip.
This matters for tariffs and export controls, and the resulting determinations have been a persistent source of disagreement between governments and industry alike.
Concentration is the standing risk
Each stage benefits from enormous scale, which pushes it toward fewer and larger sites. Efficiency and fragility increase together as that concentration deepens.
Disruption at any single point propagates through everything downstream, and rebuilding capacity elsewhere takes years because plants, equipment orders and trained staff all have long lead times.
Governments including the United States have responded with subsidies for domestic fabrication, though packaging, materials and equipment remain concentrated regardless of where wafers are made.