Leo Tolstoy's epic novel, Anna Karenina, begins with the line: "All happy families are alike; each unhappy family is unhappy in its own way."

Bring on BRICS, perhaps the unhappiest family of all. The group, whose name is an acronym of Brazil, Russia, India, China and South Africa, originated when an economist predicted that these countries would dominate the global economy by 2050.

But whilst China's GDP skyrocketed from 2010 to 2021 from $6 trillion (£4.72tn) to almost $18 trillion (£14tn), the economies of Brazil, South Africa and Russia have stagnatedStopped growing. .

They meet this week in South Africa for a summit to discuss the future of the blocA group of countries or political parties who have formed an alliance. . But the course of negotiations will not run smooth.

India and China are engaged in an aggressive border conflict. Whilst Russia and China are autocraciesCountries run by one person or small group with complete power. , Brazil, India and South Africa are democracies - if not always functionally. And Russia's President Putin is forced to attend the summit via conference call, as South Africa would be forced to arrest him for war crimes if he entered the country.¹

On the surface, they are a mish-mash of divided interests. And yet, according to the bloc, more than 40 countries have either applied to join BRICS or expressed an interest in doing so.

In a way, it makes sense. Despite the group's differences, it makes up more than 25% of global GDPShort for Gross Domestic Product, the measure of all the goods and services produced inside a country.. And being a member offers closeness to China, the second largest economy in the world.

If BRICS were to expand, it would certainly pose a challenge to the West's dominance. As the group grows, it is likely to serve less as an alliance and more as a symbol of Beijing's growing influence, as the most dominant voice in the bloc.

But each unhappy family is unhappy in its own way. Some break up; some continue bickering in perpetuityLasting forever. ; and some come together to grow stronger.

Yes: If the group expands to take in more members, China will have increased influence over and proximity to those members. Their combined power could threaten the West's position.

No: It is an outdated bloc which should not even still exist. Its members were decided in the early 21st Century, when it looked like Brazil, Russia and South Africa would perform better than they have. Instead, their economies are stagnating.

Or... In reality, the BRICS have quite little in common, where the G7 have a lot of shared principles, ideas, rules and interests. It is not a major threat to the West.

Stagnated - Stopped growing.

Bloc - A group of countries or political parties who have formed an alliance.

Autocracies - Countries run by one person or small group with complete power.

GDP - Short for Gross Domestic Product, the measure of all the goods and services produced inside a country.

Perpetuity - Lasting forever.