Seoul
The memory and display capital.
Kernel
Seoul is the city that owns memory. Samsung Semiconductor and SK Hynix together produce roughly 70% of the world's HBM (the high-bandwidth memory that frontier-AI GPUs require) and ~60% of DRAM and NAND. LG and Samsung Display dominate OLED. The Hyundai-Kia automotive concentration makes Korea the fourth-largest auto producer. None of this was inevitable in 1970, when South Korea's per-capita GDP was below Ghana's.
Why it rose
Park Chung-hee's developmental-state industrial policy (1961–79). Forced concentration of capital into chaebol conglomerates. State coordination of technology licensing and reverse engineering. A culture of educational intensity. The strategic decision to enter DRAM in the 1980s when Japan was dominant — and to keep investing through three downturns until Japan was gone.
What it gives the world
HBM (the memory layer of every modern AI training stack). DRAM and NAND at scale. OLED displays for every premium phone, laptop, and TV. The chaebol model of intergenerational family-state-industry alignment, for better and worse. The cultural-industry export complex (Korean pop, drama, beauty) that quietly funds much of the country's soft power.