A cold war is being waged across the world’s most advanced industries. And it just got a lot chillier.

Recent tit-for-tat trade actions could deepen what has become a global contest for technological dominance between the United States and China, home to the planet’s largest population of internet users and a flourishing community of start-ups and innovative companies.

The Trump administration this week accused Beijing of stealing valuable technological know-how from American companies as it proposed tariffs on $60 billion in Chinese goods and curbs on Chinese investments. China responded with its own set of penalties aimed at American products.

The fight between the two countries is cleaving the high-tech realm. The world’s two biggest economies have each become increasingly protective of their own leading-edge industries, and mistrustful of the other’s. Reconciliation looks difficult. And the rising tensions could further undercut American influence in a huge and fast-changing market.