The conflict has escalated sharply for months. Now, it pits a confident Chinese leadership, alarmed by evidence of online espionage by the United States, against an awkward alliance between the Obama administration and Silicon Valley — which itself is wary of Washington but is also salivating over the huge Chinese market.

What makes this trade dispute different from others is that traditional concerns of market share and protectionism have become intertwined with the thornier issues of national security and espionage.

“We are at a bad point in a triangular drama,” said Peter F. Cowhey, dean of the School of International Relations and Pacific Studies at the University of California, San Diego. “The Chinese government is suspicious of American spying, and it wants to advance Chinese leadership in digital markets,” said Mr. Cowhey, who is a former director of the University of California Institute on Global Conflict and Cooperation and a former counselor for the United States trade representative. “Washington suspects the worst of Chinese commercial policy and is equally suspicious of Chinese digital espionage.”

The latest chapter in the dispute began when China said American tech companies had to submit to invasive audits and create back doors into hardware and software. The Chinese say the rules are a matter of national security, necessary to protect state and business secrets.

The rules, which will go into effect in coming weeks, apply only to banking technology for now but are expected to spread to other sectors. Other proposed regulations in China, like an antiterror law still in draft form, go even further and could force tech companies to hand over encryption keys — the passcodes that help protect data from prying eyes — to the Chinese government.