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.

WhatsApp and services like it perform a crucial role in the mess that is the internet.

People want and perhaps even need smaller forums for communicating.

But users are flooding into new platforms, raising tough questions about security and privacy.

And we meet a Parisian street artist who, after witnessing brutal responses to protests,

switched to depicting clashes with police.

And the authorities don't much like what his work now reveals.

First up, though.

My fellow, Americans, a moment we have all been waiting for.

In Washington yesterday, a new chapter began as Joe Biden was sworn in as America's 46th president.

I, Joseph Robinette Biden, Jr. do solemnly swear that I will faithfully execute.

The inauguration displayed the unique circumstances in which he enters office.

Surrounded by 25,000 national guardsmen, the ceremony took place with neither crowds nor Mr. Biden's predecessor.

But it still featured some familiar inaugural hallmarks, celebrity solos, and a stirring poem written for the occasion by 22-year-old Amanda Gorman.

Being American is more than a pride we inherit.

It's the past we step into and how we repair it.

The incoming administration used the moment to project an image of, well, to choose a word that was often repeated, unity. On this January day, my whole soul is in this, bringing America together, uniting our people, uniting our nation.

Mr. Biden takes office not just at a moment of disunity in America's politics, but also a moment of multiple crises among the population.

President Biden laid out at least four big challenges facing the country.

Idris Kaloon is the economist's Washington correspondent.

...