It's hard to know where to begin when trying to list Charles Ferguson's achievements. Once a software analyst at IBM, he went on to co-found Vermeer Technologies, in 1994, to create a tool for developing webpages. The tool became FrontPage, and Microsoft bought the company for $133 million. Ferguson also holds a Ph.D. from MIT and is the author of several books on technology. Most recently he has become a filmmaker, having written and directed the Oscar-nominated documentary No End in Sight, which argues that the Bush administration ignored ample warning about the challenges it would face in rebuilding Iraq. Ferguson recently spoke with Inc. contributing editor David H. Freedman about what leaders can learn from the mistakes the U.S. made after the invasion.

The film suggests that the administration unwisely ignored the experts' advice on Iraq. How do you know when to listen to experts and when not to?

One's ability to intelligently override the experts in making a decision depends on having a certain amount of experience. If you look at the Bush administration, in some cases the people making the decisions and ignoring the experts not only lacked experience with the issues specific to the Iraq war, but they had no experience running anything. Paul Bremer had been a staff guy for most of his career, and he was suddenly put in charge of running the gigantic Coalition Provisional Authority.

Tolerating dissent is another theme in the film. Is it wrong to want your team be in sync?

Internal critics may not be right most of the time, but they might have important things to say. If you punish anyone who disagrees with you--if it becomes suicidal for anyone in the organization to express concerns--then you end up with people who think in rigid ways or who just want to curry favor.

Bush and his team had an ambitious vision for remaking the Middle East. How do you know when having a vision is going to work out and when it's not?

Sometimes the time for revolution has indeed come, and it is both necessary and possible to do something dramatically different. But even in those cases, you need to take the smallest possible revolutionary steps. The first microprocessor wasn't a 64-bit, four-processing-core engine. So it's important to have a balance of vision and pragmatism. The two aren't necessarily in conflict, but they can be, and that's also a reason why you must cultivate people who have good judgment.

What about preparation? Doesn't the rapid pace of change require leaders to move quickly?

The world contains lots of unknowns and surprises, and there are times when you have to make decisions with limited information and no time to plan or prepare. But I think that argues all the more for planning carefully for the things you can plan for, so as to keep the unknowns and surprises to a minimum.