Good morning on this action-packed Monday. Mark this week on your “History of Artificial Intelligence Timeline”: The creation of DeepSeek, the Chinese A.I. sensation that we told you about last week, is shaking the technology industry to its core.

The super-efficient, open-source software is raising questions about the valuations of tech giants, including the chip maker Nvidia, with their stocks getting crushed today. Has the entire industry been wildly overspending? It’s also raising profound questions about how China may have undercut America’s most critical economic advantage on A.I. by making its technology free. We have more on all of this below.

Plus: Wall Street should pay attention to comments President Trump made late Friday that have flown under the radar.

The DeepSeek effect

Markets are on edge on Monday, as global tech investors face a $1 trillion wipeout. The cause: anxiety that the emergence of powerful — and cheap — Chinese artificial intelligence software could upend the economics of A.I.

Nasdaq futures have plummeted nearly 4 percent. And shares in Nvidia, the chipmaker whose processors help train and run A.I. software, are down 11 percent in premarket trading. Those in Constellation Energy, a utility betting heavily on powering A.I. data centers, are down nearly 13 percent.

Meanwhile, tech executives and policymakers have been left to wonder how strong America’s lead in A.I. is.