In one version, a single head chef controls every recipe, every oven, every topping in every location — that's a unitary system.
In another version, each regional kitchen gets to decide its own specialty pies, its own hours, its own local flavors, while the parent company still sets food safety standards and manages the brand — that's a federal system.
Countries like Mexico, Nigeria, and Russia chose federalism because they're vast, diverse places where a one-size-fits-all approach would ignore the real differences between communities.
By splitting power between national and local governments, they let regions handle things like schools and social services in ways that fit their people, while the central government manages defense, currency, and foreign affairs.
On the other hand, China, Iran, and the United Kingdom concentrate authority at the national level, which can mean more uniform policies and faster decision-making — fewer cooks negotiating over the recipe.
Here's what makes this really interesting: these systems aren't frozen in place.
Russia has centralized power dramatically under Putin, while the UK has devolved significant authority to Scotland and Wales.
Internal pressures like ethnic divisions, or external forces like the European Union, constantly push countries to rethink how much power stays at the center versus how much flows outward.
The label on the box matters less than what's actually happening inside it.