Most unicorns get so big from network effects so I suspect they play a similar role to language. The social connected graph is a lot less connected across Eur

Most unicorns get so big from network effects so I suspect they play a similar role to language. The social connected graph is a lot less connected across Europe than across the U.S. Imagine starting a Facebook in Germany versus the U.S. Spreading from state to state is easy because there is a large amount of media and social overlap. If you have a successful startup in California its much easier to spread to Texas, New York, Florida, and Illinois than to spread from Germany to England, France, Italy, and Russia.