SINGAPORE—The unexpected success of Chinese AI startup DeepSeek has revealed cracks in U.S. efforts to contain China’s technology ambitions, challenging both Washington and Silicon Valley to rethink how best to preserve American supremacy.

The emergence of the DeepSeek chatbot has sent Silicon Valley into a frenzy, with calls to go faster on advancing artificial intelligence and beat communist-led China before it is too

For the second time in the last month, a Chinese app has skyrocketed to the top spot in Apple’s App Store. The first was Xiaohongshu, or RedNote, which saw a sudden surge in downloads by United States users seeking an alternative to TikTok in anticipation of the ban on that app,

Technology shares steadied, led by a modest recovery in Nvidia after its record-breaking wipeout in market value.

The success of a mysterious Chinese lab has investors questioning the AI spending boom that has swept through Silicon Valley.

DeepSeek, a young Chinese AI startup, triggered a steep sell-off in U.S. tech stocks Monday as its cost-effective AI models raised doubts about the vast investments by American tech giants in artificial intelligence.