balkaniser

To balkanize — to fragment a country, organization, or field into small, often mutually hostile units. A formal, journalistic/political term, now also used figuratively for any fragmentation (balkaniser un marché, un débat).

• Certains craignent que ce projet de loi ne balkanise le pays. — Some fear this bill will balkanize the country.
• Le marché s'est balkanisé en une multitude de petits acteurs. — The market has fragmented into a multitude of small players.
• Les experts parlent d'un secteur balkanisé et peu coordonné. — Experts describe a balkanized, poorly coordinated sector.

This is a formal, journalistic register word — using it in casual conversation about splitting something ordinary would sound absurdly grandiose; fragmenter or diviser are the everyday choices.

• politics Balkanisation — Coined in this figurative sense by German industrialist and politician Walther Rathenau in a December 1918 New York Times interview, describing the early-20th-century fragmentation of the Balkans into small states.