Jeremy Grantham calls this the most dangerous market peak ever

There is one thing about this market that keeps showing up.

The biggest warning signs are not coming from people saying AI is fake.

They are coming from people saying the AI story might be real… but the money going into it could be getting ahead of reality.

Legendary investor Jeremy Grantham is warning that this could be one of the most dangerous market peaks because of the AI bubble.

His argument is that we have seen this pattern before.

Railroads. Internet fiber. Huge investment waves that changed the world, but also created massive overbuilding before the market eventually corrected.

And now AI spending is moving at incredible speed.

At the same time, valuations are sitting at extreme levels compared with GDP, profit margins are near historical highs, and liquidity conditions are starting to weaken.

The interesting part?

The market is not waiting for the data to look bad.

History shows markets often move first, then the official numbers catch up later.

Meanwhile, 80% of global investors say being long semiconductors is the most crowded trade, close to a record level.

Everyone is looking at the same AI winners.

Everyone expects the same story.

And that is usually when the market gets interesting.

Because the biggest question is not whether AI changes the world.

It probably will.

The question is whether investors already paid for a perfect future.