More than half of all Americans said they would change their driving habits or lifestyle if the cost of gasoline rose to $4 per gallon, new AAA survey data shows. The survey, conducted last week when gasoline was "just" $3.50 per gallon, showed that two-thirds of Americans felt gasoline prices were already too high. Fifty-nine percent of those surveyed also suggested that they would change their driving habits or lifestyle if gasoline reached $4. We have now arrived and surpassed that level, although time will tell whether those intentions...