One effect of Donald Trump’s sanctions on China’s tech giant Huawei seems to be a growing nationalistic sentiment among some Chinese consumers: sales of iPhones have fallen in recent months, while Huawei products have seen an uptick. It isn’t hard to find patriotic slogans backing the embattled company on social-media platforms such as Weibo.

It’s not surprising, but it is part of a worrying trend. It’s the latest sign of how America’s foreign policy, and tensions with China especially, are threatening to carve up the tech world along national boundaries.

“We are already seeing the balkanization of technology in many domains,” says Zvika Krieger, head of technology policy at the World Economic Forum. “If this trend continues, companies will have to create different products for different markets, leading to even further divergence.”