be really expensive, and so I thought to myself: what activities have human cultures engaged

in, in the past that were as expensive as what it might be to go to Mars and what motivated

them to spend that money? I was going to fill a whole book, "Motivations to do Great Things,

Great Expensive Things," and then I'd find the task, I'd find the activity that most

closely resembled what it would be to go to Mars in the 21st century and I'd say, oh,

is that what that culture did with their population, is that how they raised the money, is that

how they convinced the people? I was going to fill a whole book of this. It would be

a nice little reference catalog about how to get something done in modern times.

In conducting that exercise what I found is that there are only three drivers, not more,

not less, three drivers that account for the most expensive, ambitious projects humans

have ever undertaken. One of them is the praise of deity or royalty. That's what got you the

pyramids. They're basically expensive tombstones. That's what got the cathedral and church building

of Europe. That was a period where huge fractions of societal investment went into those activities.

There is less of that today, so that's not really a useful driver to think about how

we might transform the 21st century. Another driver is war. Nobody wants to die. That gets

you the Great Wall of China. That gets you the Manhattan Project where we built the bomb.

That gets you the Apollo Project. Another driver, the search for economic return—nobody

wants to die, nobody wants to die poor. The search for economic return, that's what is

responsible for the Columbus voyages, the Magellan voyages, Lewis and Clark figuring

out what is beyond that frontier in hugely expensive enterprises, conducted by governments.

So if we're going to go to Mars, and if war is not the driver—because it could easily

become the driver if you get another space race with someone we view as a military adversary;

I wonder who that might be—but if peaceful heads prevail, then war is not the driver

available to you. Let's check our list. Well, kings and gods are not sufficient in modern

times to undergo heavy projects such as that. What's left? The promise of economic return.

You can go into space, transform society, change the zeitgeist of your culture, turn

everyone into people who embrace and value science, technology, engineering and math,

the STEM field. Whether or not people go into space or serve the space industry they will

have the sensitivity to those fields necessary to stimulate unending innovation in the technological

fields, and it's that innovation in the 21st century that will drive tomorrow's economies.

Any frontier in space now involves biologists—we're looking for life—, chemists, geologists,

physicists, mechanical engineering, electrical engineers, aerospace engineers, astrophysicists,

all the traditional sciences and engineering frontiers are captured in any ambitious goal

to explore space. We can recapture those times and reinvent America. We've already invented

America once before. It's ripe. It's ready and it's willing, I think, to be invented

again.