Nobody would argue that speculation wasn't a problem, but it was only part of it.
People speculated that as the price went up and people would continue to drive --- that is until a breaking point was reached. Well, we hit that point and demand dropped sharply. Because of the strain high oil prices put on the markets, economies worldwide failed and/or are failing.
Had the US been producing its own oil and flooded the market when the speculators tried to get the price up, the price of oil would have gone back down.
But don't worry, the likely next administration isn't very oil friendly, so, watch for oil to go back up as the markets stabilize and recover and as a result demand goes back up.
-Fatty