Funny, after talking about corporate diversity , the SJ Mercury News published an article today about Santa Clara County's even racial mix (Mike Swift, front page). Apparently, no racial group is more than 40% of the total population. But here's the best line, from Michael Cornwell: "It's all just Silicon Valley: Let's make money and be happy." I couldn't have summed up Santa Clara County better.
As for diversity, we are diverse because we have been able to attract educated immigrants, who happen to be from non-white countries. Any capitalistic system requires more immigration to sustain itself. In a capitalist system, there will always be many poor people trying to get out of the vicious cycle of poverty--that's the unequal nature of the beast and also its salvation. Immigrants increase demand and give money or work to existing residents wherever they go. Capitalist countries should increase immigration so demand for services, products, and real estate also increase, allowing people already here to benefit. Once the new immigrants--who have to spend more money, buy or rent real estate and otherwise participate in the economy--save enough money, it's time for the next round of immigrants to come in and create more demand.
America's low population density allows capitalism to be successful. The EU, especially the UK, with its limited land area, will have difficulty sustaining its move towards a more capitalist system, because at some point, real estate will get so expensive new immigrants will be unable to afford it. In contrast, America can keep adding millions of people every year without difficulty. The sparsely populated Midwest, especially, ought to be trying to attract educated immigrants from all over the world. You can argue about legal or illegal immigration--but you're talking about form, not substance. Every capitalist system needs more immigrants unless it wants to create massive, perpetual inequality. Being pro-capitalist means being pro-immigration, because immigrants create instant demand for numerous services and products. As long as these immigrants are able to get jobs, save money, and buy homes, they will successfully integrate into society. Then, it's time for the next round of immigrants to enter and keep the cycle going. In the long run, because of the perpetual danger of the majority population lapsing into "the other" mentality, it's hard to be pro-immigration without being pro-capitalism. A capitalist society, where income streams are highly diversified, allows at least some immigrants to make money no matter what their government's policies.
In contrast, socialist systems need to be more careful with immigration, ensuring they do not attract more people than they can assimilate. France's riots reveal what happens when a socialist system attracts and invites too many immigrants--the lack of jobs to go around breeds resentment and anger. Ultimately, socialist systems and welfare states can work quite well--see Scandinavia, for example--but only in homogeneous situations hostile to immigration and with low birth rates (or, in the case of China, a one-child policy).
America's openness to immigration and its ability to absorb immigrants are the primary reasons we are successful and continue to be different from the European slower-growth model.