Amid the cactus in the Arizona desert outside Phoenix, a series of extraordinary buildings will shape the future of the global economy and the world.

The buzz of further construction is not only about creating factories for the world’s most advanced semiconductors. Ultimately, it will produce the world's most advanced chips on a large scale. The work was first completed in the United States, with the Taiwanese company behind it pledged to spend billions here to promote tariff threats to import chips.

I think this is the most important factory in the world, it is built by a company you have never heard of: Taiwan semiconductor manufacturing company TSMC. It makes 90% advanced semiconductors. So far, they have been made on mainland Chinese islands in Taiwan. Apple chips in iPhone, NVIDIA chips power your Chatgpt query, chips in laptops or computer networks, all made by TSMC.

Its Arizona facility, “Fab 21,” is strictly protected. If the design leaks, blank paper or personal devices are not allowed. It owns some of the most important intellectual property rights in the world, and the process of manufacturing these chips is one of the most complex and intensive processes in global manufacturing.

They are very protective of internal secrets. Important customers such as Apple and NVIDIA believe the company can protect the design of its future products.

But after months of inquiry, TSMC has asked the BBC to take a look at the transfer of some of the world's most critical, expensive, complex and important manufacturing.

Of course, President Trump seems to think so. He often mentions factory passing. "TSMC is the biggest," he said. "We gradually lost our chip business and are now almost entirely in Taiwan. They stole it from us." This is a regular rejection by the US president.

TSMC recently decided to increase its investment in the U.S. by another $10 billion (£75 billion) as Trump attributed to his tariff threat to Taiwan and global semiconductor businesses.

He believes the expansion of Arizona facilities announced in March is that it is a poster of its economic policies for kids — especially foreign companies moving factories to the U.S. to avoid encouraging huge tariffs.

China is also paying close attention to development. Taiwan’s chip-making capabilities have become part of what the government calls “silicon shield”, opposing the harsh invasion. While the initial strategy was to make Taiwan essential in this critical technology area, the difficulties of the pandemic supply chain changed calculus because relying on a country seemed to be a greater risk.

Therefore, many of the flows of the world economy, border technology and geopolitics flow through this location, which is the fundamental contradiction between Trump's economy and foreign policy.

He believes that the plant is a model for the United States and preserves its economic and military advantages over China. However, in the fields of physics and chemistry, the manufacturing of these modern miniaturization miracles essentially relies on the combination of the best technologies around the world.

Greg Jackson, one of the facilities managers, brought me to the golf cart. These factories are almost carbon copies of Taiwan's TSMC space, where he trains. "I would say these facilities are probably the most advanced and complex in the world," he said.

"It's quite dichotomous. Your structure is really small, your chips are very small, it comes with a huge facility with all the infrastructure to make them...just pure complexity, the number of systems being used, which is really shocking."

Before crossing the bridge that should create the cleanest environment on Earth, inside the "Gown Building", workers wear protective clothing to protect the production of these extraordinary microtransistors that create all the microchips that make up everything.

Engineer Konstantinos Ninios showed me some of the earliest works of TSMC Arizona: a silicon wafer with a "4-nanometer chip" on it.

"This is the most advanced wafer in the United States right now," he explained. "(IT) contains about 10 to 14 trillion transistors...the whole process is three to 4,000 steps."

If you can somehow shrink the body to the same scale and go into the wafer, he said many different layers look like very high streets and skyscrapers.

TSMC was established in 1987 at the request of the Taiwan government, when Chip Execuceion Morris Chang was directed to conduct business. The model will become a dedicated foundry for microchips – manufacturing designs by other companies. It became very successful.

Promoting technological advancements is the miniaturization of the smallest functionality on a chip. Today, their size is measured in billions of a meter or nanometer. This progress has enabled mobile phones to become smartphones and is now setting the pace for the massive deployment of artificial intelligence.

By using “extreme ultraviolet (UV) light,” it requires incredible complexity and expense. This is used to etch complex building blocks of our modern existence in a process called “lithography.”

The world’s reliance on TSMC is built on highly professional bus-sized machines, which in turn comes almost entirely from a company called ASML, including Arizona.

These machines shot tens of thousands of UV light through drops of molten tin, thus producing plasma, which was then refracted through a series of professional mirrors.

In a few months, thousands of nearly fully automated processes of silicon were repeated over the course of several months, then before forming a $1 million-sized wafer of a $1 million 4nm silicon chip.

"Think about particles or dust particles," Niños said to me incredibly. "The transistors don't work properly. So all of this is cleaner than the hospital operating room."

Taiwan does not have special access to raw materials – however, it has the expertise to stay ahead of the complex process of producing these atomic building foundations for modern life.

Some in the Taiwan government have carefully spread the borders of the technology to the island. Trump has little time to claim that the company's decision to bring its highest level of technology to the United States was due to his economic policies.

He said that this would not have happened without the paste of tariffs he planned on Taiwan and semiconductors. The people I talked to at TSMC are diplomatic about this.

Under the "Bargoing Chip Act" of former US President Biden administration, plans and subsidies have been planned.

Photos on the sidewalk leading to the building show Biden’s visit in 2022, with construction sites paved on stars and stripes and saying “the future of America.”

“The semiconductor supply chain is global,” said Rose Castanares, president of TSMC Arizona. “At present, there is actually no country that can do everything from chemicals to wafer manufacturing to packaging, so it’s hard to quickly relax the entire process.”

As for semiconductor supply chains, tariffs are of no help. The supply chain extends worldwide. Whether it is silicon wafers from Japan, machines needed in the Netherlands, or mirrors from Germany, they all require various materials from all over the world. Now, they can face import fees.

That is, the boss of TSMC confirmed that the expansion of the US website was fast at an event with Trump at the White House. In recent weeks, the U.S. tech elites — from Apple’s Tim Cook to Nvidia’s Jensen Huang — have been lined up to tell the world that TSMC Arizona will now produce many chips in its U.S. products.

The global chip industry is very sensitive to economic cycles, but its state-of-the-art technology has very healthy profits that can buffer tariffs on some of these plans.

There are many geopolitical subtexts here. The factory is located at the heart of the U.S. strategy to gain access to technology, artificial intelligence and economy in China.

Both Biden and the Trump administration have put in place policies that attempt to limit China's access to border semiconductor technology—from banning machines exported to ASML to new legislation that prohibits Huawei AI chips in U.S. software or technology anywhere in the world.

Taiwan President Lai this week urged democratic countries such as Japan and the United States to develop "non-red" supply chains to oppose China.

However, not everyone believes that this strategy is working. Chinese technicians have been effective in developing competitive indigenous technologies around the ban. Bill Gates said this week that the policies “force the Chinese to move forward at full speed in chip manufacturing and everything.”

Trump hopes Arizona TSMC will be the foundation of the American golden age. But the company’s story so far may be the ultimate expression of the success of modern globalization.

So for now, this is a battle of global technology and economic supremacy, where Taiwan’s factory technology (most of which are now being transferred to the Arizona desert) is a key asset.

Top image source: Getty

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