That's a good point. Invading Gaul et al. was probably more lucrative than invading a country like Afghanistan as the Romans were more obviously and unabashedly imperialistic and that war had to do with territorial expansion.

The invasion of Gaul is more akin to the way (relatively) early Americans forced out the Native Americans, and their culture certainly changed/doesn't really exist anymore. WWII Japan and Nazi Germany are examples of a places where a short war changed the culture.

The reason it won't work any more is because that style of 'total war' appears to have gone out of style. Probably a good thing, though Fareed Zakaria was on the Daily Show the other night talking about how one reason America has been so powerful is because Europe was leveled in WWII and the US had the industry to rebuild.

> it took hundreds of years

Compared with a few years for the wars. That's the point - it's easier to wage war than to change a culture.

Another interesting book along these lines is this one:

A Language History of the World http://t.co/f80cwQo

It uses languages to look at where they 'stuck' and where they didn't, why, how, and so on.

It's probably an exaggeration but I believe Caesar's Gallic Wars has something about killing a third of the Gauls and enslaving another third.

Implacable patience would almost certainly substitute for a certain amount of brutality, but the more of one you have the less you need of the other.