This key decision made by Roman generals?

To design military chariots to be as wide as the behinds of two horses. This meant placing the wheels 56.5 inches apart. This would guarantee that the chariot could not be hung up on defenders or their obstacles. Instead, the chariot and its two soldier passengers could move as far and as fast as two horses could move.

All chariots made for the Roman army were built to this identical specification. All the wheels were exactly 56.5 inches apart, even though horses' rumps might be fatter at the start of a campaign than at its finish.

With Rome overrunning and occupying much of the world, Rome built roads everywhere. The fast transport of soldiers on chariots helped Rome control its vast empire.

But because the roads were not paved, the chariots' wheels made ruts in the roads – all ruts being exactly 56.5 inches apart.

Naturally all the world's wagon makers decided to build wagons which would easily fit into the ruts made by the Roman chariots. As a result, all wagons were built with wheels which were exactly 56.5 inches apart.

When the railroad era dawned in the 19th century, many wagonmakers switched to making railcars. And, just as naturally, they converted their factories to making freight and passenger cars with wheels which were 56.5 inches apart. This spared them huge costs which would have been necessary if they had been required to completely retool their plants.

The great railroads in the U.S. were built on tracks carefully laid out 56.5 inches apart. Bridges and tunnels were built to accommodate these rails.

Unfortunately. tunnels were built to accommodate the width and height of horse-drawn carriages – and freight cars. Thus tunnels would severely restrict the width of the freight traveling by rail.

How is this important?

The rockets NASA uses in space are not as wide and as powerful as the agency would like.

NASA could build bigger rockets, of course.

But bigger and more powerful rockets cannot pass through the tunnels interspersed between the factories and the launch sites.

As a result, we build and launch smaller rockets than we would like.

All because of a decision made about the size of horses' behinds.

No Roman general could have predicted that his chariot specifications would affect American rocket building 2,000 years later. (At the time Rome believed the world was flat and that the sun revolved around the earth.)

If you did not understand chaos theory before, this example should help you along.

Chaos theory is a lot more than a bird pumping its wings and affecting weather patterns.

I wonder which decisions being made in Washington today will affect the world 2,000 years from now.

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