The semiconductor industry has evolved significantly in the last 50 years. While in early 60s, US was the clear market leader, by the 90s the semiconductor industry in Taiwan, Singapore and Korea posed a competitive threat to that in the US. Recent times have witnessed other locations in China and India establish themselves firmly on the global semiconductor landscape.
For any innovation hub, the entire ecosystem has to be favorable for growth. This includes access to large skilled talent pool, strong university ecosystem, favorable government policies etc.