I laid out the gloomy picture for Silicon Valley yesterday, as conceived by a savvy group of public company CEOs. They were far more pessimistic than I expected, and I think their thinking sounds a warning klaxon for the Bay Area. But the very darkest scenarios don’t convince me, for a number of reasons.

First, endism is always suspect. I return from time to time to Paul Duguid and John Seely Brown’s wonderful Social Life of Information. One of their lessons is the dangers of extrapolation, particularly well into the future. A few technology companies are shifting resources from Silicon Valley to Asia, and some are even wondering further down the line about an Asian listing, getting out from the onerous demands of US markets. That doesn’t necessarily mean we’ll witness a flood of companies shifting out of the Valley in coming years. JSB and Duguid warn us not to count one, two, three… infinity. Shifts don’t happen in a neat, linear fashion. There is more inertia than most people credit in systems, and as change happens, it gets modified by changes in culture, technology, politics and society. That doesn’t make for such a great headline, but it’s a better reflection of reality.

Second, there still is a distinct US advantage for innovation and risk-taking. We’re not the only innovators, but what Howard Rheingold calls our “wild-ass culture” remains an outlier among nations. And that wild-ass culture isn’t evenly distributed across the nation. One of the CEOs in my group on Wednesday was from India — as is often observed, around 50% of Silicon Valley start-ups are led by immigrants — and he believed strongly that the Bay Area remains non pareil for innovation. There’s the critical mass of experience and expertise, high tolerance of failure, and the necessary capital to make things happen. It’s been fascinating to observe the many attempts both in the US and internationally to replicate Silicon Valley. They assemble capital, good universities and a critical mass of engineers and scientists, and… are disappointed. New, powerful technology clusters are emerging in Bangalore and Shanghai, but it’s clear that there can’t be dozens of Silicon Valleys. Perhaps three is what the globe can handle.

Third, and here I part dramatically from the CEOs I sat with on Wednesday, I’m hugely optimistic about what the Obama administration is going to do for the US. I remain a near- and medium-term pessimist about the economy, but we’ll eventually emerge from the Great Recession. When we do, the renewed support and emphasis on science and technology — on reality — offers an opportunity to return to the spirit of my youth when the best and brightest wanted to become scientists and engineers, not financiers or lawyers. The challenge of effective action on climate change certainly provides a staggering goal for the ambitious. Finally, I’m hopeful about the resources and thinking the administration is putting into rescuing our public education system.

A better education system remains the key to any optimistic view. Imagine a country where children are encouraged to exercise their imaginations and take risks. Where the goal isn’t more homework, but more signs of initiative and independent thinking. That creates a system that makes the most of America’s advantages, rather than try to create a pale imitation of Singaporean or Chinese education. There are numerous paths to national well-being and prosperity and I think we have a chance to chart one that is uniquely ours.