China, the world’s largest mobile market by subscriber and network size, is determined to become the world leader in 5G wireless technologies, posing a new competitive challenge to Western telecommunications firms and raising national security concerns for Western governments. So says The South China Morning Post this week in one of a flurry of recent accounts detailing the escalating global arms race in next-generation mobile networks.

“If ‘big data’ is the new oil of the digital era,” the Post observes, “then 5G is the next set of pipes that will deliver it—and unlike previous generations, China is determined to own more of this infrastructure, giving it mastery of its own industrial future.”

The stakes are high. 5G networks are expected to be about 100 times faster than current wireless networks. They promise movie downloads in the blink of an eye and an explosion of new mobile services. Champions of the new networks say they will support a riot of connected devices, and unleash unimaginable breakthroughs.

Some experts think China is winning the 5G race. Beijing identified 5G as a national priority in its “Made in China 2025” technology roadmap and worked closely to set global technical standards. The government supports efforts of its mobile carriers and equipment manufacturers to develop 5G technologies. Huawei Technologies, China’s largest telecom equipment maker, is investing billions in 5G research and owns a critical patent for “polar coding,” a breakthrough method for correcting errors in data transmission invented by Turkish scientist Erdal Arikan. A recent Deloitte study found that, since 2015, China has built 350,000 cell sites compared with fewer than 30,000 in the US. China is expected to roll out 5G for commercial use in 2020.

The U.S. has left development of 5G to the private sector. AT&T (T) and Verizon (VZ) are rushing to introduce 5G in some U.S. cities by the end of this year, but mobile devices compatible with the those new networks won’t be available until 2019.

The Trump administration has focused on 5G networks in its wider dispute with China over technology and trade. Washington has barred China’s two largest telecommunications equipment makers, Huawei and ZTE, from competing in the U.S. market, citing national security concerns, and sought to deter strategic allies including Australia, New Zealand, Canada, and the United Kingdom from accepting 5G services from Chinese telecommunications equipment companies.

All told, the battle for dominance in high-speed wireless offers yet another example of how competition between the planet’s two largest economies is cleaving the world into two (or possibly three) rival techno-blocs.