Hello and welcome to the Intelligence on Economist Radio.

I'm your host Jason Palmer.

Every weekday we provide a fresh perspective on the events shaping your world.

How soon do you want your online shopping delivered?

Two days, the next day, an hour?

How about before you've even ordered it?

Amazon has transformed shipping and big retailers are following suit.

Behind the scenes, that's radically transformed how stuff gets around the world.

And the biggest traditional toy maker in China isn't homegrown.

It's Lego.

We pay a visit to a bustling flagship store in Shanghai to ask why the Danish bricks are so much more popular than other toys.

But first...

America's democratic primary debates kicked off last month.

Tonight, the second round begins.

And the stage will again be crowded.

Twenty out of 25 candidates will participate over two nights.

And of the four frontrunners Elizabeth Warren will take on Bernie Sanders tonight.

Tomorrow, it'll be a rematch for Joe Biden and Kamala Harris.

But each evening, there will also be eight other candidates fighting to stand out.

The slate of 25 hopefuls could fill two football teams.

It could be the primary cast for a Broadway musical.

In the 20th century, such a crowded field would have been unusual.

...