We all know China is a huge — or potentially huge — market for U.S. tech goods. We also know that geopolitical realities have restrained trade with China — which is why Huawei has very little presence in the U.S. and also why Cisco(s csco) has seen its market share in China decline in the past few years.

Revelations that the U.S. National Security Agency and its “Five Eyes” analogs in the U.K., New Zealand, Australia and Canada now pose additional hurdles to these U.S. suppliers as they try to sell in China. According to a new research note by Sanford Bernstein’s hardware and software analysts:

“While spying has occurred across many companies, governments and corporations, we believe U.S. technology companies face the most revenue risk in China by a wide margin, followed by Brazil and other emerging markets.”

The degree of risk faced by U.S. providers in China depends on…