Story highlights From Bogota to Moscow to Milan, cities around the world aspire to be the next Silicon Valley

Bob Dorf: This is both a noble aspiration and a near-impossible dream

Bob Dorf, a serial entrepreneur-turned-startup educator, co-authored "The Startup Owner's Manual" with Steve Blank. He teaches entrepreneurship at Columbia Business School and trains and coaches early-stage startups around the world. The opinions expressed in this commentary are solely those of the author.

(CNN) From Bogota to Moscow to Milan, cities around the world aspire to be the next Silicon Valley. This is both a noble aspiration and a near-impossible dream.

The catalyst that turned the valley into what it is today is one that nobody should want: World War II. In the 1940s, the best and brightest engineers were tasked with inventing technologies that can help the United States win the war. Stanford was a hub for tech talents and over the decades transformed the valley into an ecosystem for countless electronic and software companies.

Bob Dorf

So what keeps the rest of the world from catching up to Silicon Valley? From the entrepreneur perspective: Not enough mentors, talents and far too few risk-taking investors in early-stage startups.

Where are the mentors?

Outside of Silicon Valley, there are far too few startup founders who serve as role models. It's hard to walk down University Avenue in Palo Alto, for example, without literally bumping into a handful of successful founders or early employees who've enjoyed the thrills, rewards and learning that comes with building a great company.