THis is a very easy question:

Outside of the US, it is very expensive to own and operate a car. The cars themselves are very expensive, gas is even worse. That being said, it is almost a luxury to have a car, and driving is considered a skill to have. Manaul cars are less expensive (usually) AND they offer the driver more control over the car, hence when you add up all of those factors, manual tranny's are more popular. (In the UK it costs a significant amount of money to pay for FORMAL TRAINING to even get a license, it's not like in the US where every kid gets a permit as soon as they're old enough and have had absolutely zero training). Also outside the US, gas is so damn expensive that all of the cars have tiny little engines, and until recently many didn't even have airconditioning. If you put an automatic in a car with a small engine and an ac compressor, you could probably walk faster. Remember, the US is the land of V6's and big V8's that can move a car with a slushbox.

Why are automatics more popular in the US?
1) easier to drive in our overly congested roads
2) driving isn't a skill to be obtained for everyone, it's a necessity to be obtained in order to live your life
3) the quantity of people in the US who need a car and see it as a necessity or basic form of transport and not a skill far outnumber the # of people who feel the same way in other countries.
4) gas is cheap
5) engines are big

In the US, anyone can get a license and drive some sh*tbox around, outside of the US it's too expensive and not available to the masses (overall).

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