Great inventions have often brought a rush of investment. Sometimes, it ends in a crash.

Some experts fear artificial intelligence is heading the same way.

Hundreds of billions of dollars are pouring into AI,  far ahead of the profits it can deliver.

Last week, investors blinked.

The Democratic Party swept the US midterm elections, and some of its candidates had called for tighter rules on data centres that power AI.

Fears of a slower buildout wiped trillions of dollars off stock markets. They have only partly recovered.

The stakes reach far beyond Wall Street. Pensions and growth are riding on the AI boom.