India, Nov. 8 -- A bond is a boring instrument until it is not. Earlier this year, CoreWeave, a company that builds and rents data centres for artificial intelligence (AI), borrowed at around 10 per cent. On Friday, bond investors demanded more than 16 per cent to lend to the same company. Six percentage points is the distance between a boom and a doubt. Credit markets had been whispering that doubt for weeks. The American midterm elections of November 3 turned the whisper into a shout.

The sequence matters. On Tuesday, Democrats won both houses of Congress and the governorships of Texas, Ohio, Georgia and Michigan. Dozens of local ballot measures across ten states, nearly all seeking restrictions on data centre construction, passed. On ...