system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why Russian rockets have branching thrusters, while American ones don't.
gpt
The Soyuz rockets used technology directly derived from the V-2 missile. The problem the Soviet engineers faced when making the R-7 launcher  for the Soyuz was that, when they attemted to scale the engine larger, the engines became more unstable. They began stuttering and exploding. 

The US took years to  solve this problem in the F-1 engine program, which were used in the in Saturn Rockets.

The Soviets engine designers solved the combustion instabilities by using  one large powerful turbo-pump that feed four small chambers instead of a one large. This resulted in more stable combustion. Which, allowed for a larger and more effective turbo-pump.


The Russians have kept this concept of clustering many small chambers  and feeding them with a common turbopump.  The RD-170, the world's most powerful liquid-fuel rocket engine, use the same idea of using four smaller chambers feed by a common turbopump.