Earlier this month, defense technology company Mach Industries raised $600 million in a Series C financing round, raising its valuation to $3.7 billion.

This is more than double the $1.8 billion valuation achieved by Mach just three months ago when it completed its initial $300 million Series C financing; that round of financing was led by Ribbit Capital, Infinite Capital, Bedrock Capital, and Sequoia Capital. However, what may be even more noteworthy than the speed of financing is the age of the person in charge of this company: a 22-year-old individual is at the helm of this firm, which develops autonomous defense systems.

The founder and CEO, Ethan Thornton, founded Mach in 2023 at the age of 19. He had developed an interest in national defense during his teenage years. Since then, he has built the company around the principles of rapid action, willingness to take risks, and continuous adaptation to the evolution of the company's technology and the broader defense industry.

Thornton said to Fortune, "You can never know everything, especially when you are young and just starting a business, and you shouldn't expect to know everything either. If you wait until you have all the answers before you begin, you might never get started at all."

By 2024, Mach reached an agreement with the U.S. Army Applied Laboratory to develop a vertical takeoff and landing precision cruise missile – since then, the company's development momentum has continued to accelerate.

Today, this Gen Z entrepreneur manages a company with six weapon projects, a headquarters and manufacturing facilities covering 115,000 square feet in Huntington Beach, California, and aspires to create a variety of products ranging from aircraft bodies and jet engines to solid rocket engines, energy-containing systems, and autonomous technologies.

The backdrop for the company's rapid growth is a broader upsurge in defense technology. Fortune reported earlier this year that in just the first quarter of 2026, investments in this field reached a record $19.8 billion. However, Thornton is betting that Mach can not only ride on this wave. After several years of technological development and testing, the company is now shifting its focus to production.

Thornton said to Fortune, "For companies like Mach, private capital allows us to take risks earlier. Even if there isn't a large project behind a certain technology, we can still create it, test it, learn from it, and make quick changes. Moreover, since we consider solving problems from the very beginning, we don't design something first and then think about how to produce it years later. We are building both the product and the production capacity at the same time."

Turning a childhood interest in military affairs into a defense technology unicorn

Thornton's interest in national defense began long before the establishment of Mach – even before he reached the age to drive.

Thornton grew up in a military family in Texas. Over time, he became increasingly concerned about China's rise and what he described as "an imminent major power conflict." By the age of 16, he was already making prototypes for defense applications on his parents' land, using materials purchased from Home Depot and Amazon to test hydrogen-powered weapons.

Later, he took this interest with him to the Massachusetts Institute of Technology (MIT), where he studied aerospace engineering (and even made it onto the football team). At the same time, he worked at Lincoln Laboratory, a defense research center funded by the federal government at that institution. Before completing his first academic year, Thornton received a Thiel Fellowship scholarship and left MIT to devote himself full-time to his own company.

Mach quickly caught the attention of Silicon Valley. In June 2023, Sequoia Capital led a $5.7 million financing round for Mach; this was the first time that venture capital firm had invested in a hardware defense technology company. Sequoia partner Stephanie Zhan, who led this investment, summarized the ambitions of Thornton at the time as follows:

Zhan represents: " Ethan possesses an unstoppable energy; whether it's his technical depth, his almost obsessive dedication to problems, his tendency to prioritize action, or his maturity that surpasses his age. Defense technology is crucial for our security, and Mach represents a leapfrogging advancement in the current state of the industry."

However, for Thornton, the experience gained from creating Mach at such a young age does not lie in possessing all the answers, but in knowing whom to have around oneself.

He said, "Find people who are stronger than you in areas you don't understand, those who will challenge you and who believe in what you want to create."

Thornton's core advice to other young people with grand ideas is just as straightforward: don't be afraid of failure.

He said, "You must be willing to learn as you move forward, make mistakes, and then keep moving on. Maintain faith in the problem you're trying to solve, and then surround yourself with people who can help you solve that problem."

Preston Fore

X: @ forepreston

Email: preston.fore @ fortune.com