Doom and gloom are always popular on this forum, but in fact, gasoline prices are still not particularly high when adjusted for inflation.

The long-term average pump price since 1918 was $2.39/gallon. Gas was extremely cheap in the 1990s and early 2000s. For example, the price in 1998 was only $1.36. In contrast, the price in 1918 was $3.61, and prices didn't dip below $2.50 until after 1945.

This means that during the decades that saw the most rapid increase in motoring (1920 - 1940), prices were actually higher than they are now. It seems likely that prices will have to go quite a bit higher before their is a large drop in consumption. However, in 2008 there were small drops in gasoline consumption when prices briefly peaked at around $4.00, although average prices for the year were only about $3.20.