I second that. In addition, most of those companies use a portion of their revenue to buy back their shares, pushing their price up. So, the value created worldwide ends up growing the US stock market.
Ths stock market is not considered in GDP. So by that measure it does not directly impact "economic growth." I can see an indirect relation that says that US investors (primarily through pensions and 401Ks) are the primary benefactors of a growing US stock market which then translates to more investment and opportunity of US citizens, but that is a pretty long trail to account for our economic path right now.
And then even more specifically - at least in terms of local problems - that pushes up the value of compensation for a lot of people in the SF Bay Area which inflates the cost of land there.
Staying out of whether or not the concentration is a problem at the national/international level, is there any realistic alternative short of massive protectionism a la China to force home-grown tech companies in other parts of the world?
The US has a massive advantage of being the largest economy, having a vast single market, issuing the world's reserve currency, and having unique hubs like the Bay Area attracting the best and brightest. It would be hard to replicate its success elsewhere without having some of the above prerequisites.
>being the largest economy, having a vast single market
America is NOT the largest market the EU is MUCH BIGGER. And it is not "America" that commercialises technology, but a small portion of California called The Valley.
