Sub, I honestly don't understand your post.
Does "big oil" make any more profit with the price of gas at $4? No. They make 8-9 cents/gallon. As one oil exec said at the most recent inquisition, if they were make $9 million profit on $100 million in sales, there would be no problem. $9 billion on $100 billion is somehow a problem. Well over a hundred companies in the fortune 500 make a higher profit margin than the large oil companies.
You say the price is determined by speculators (indeed this is truthful in part), but speculation in and of itself is not evil, and I think that many people do not understand it. It is explained quite well
here.
The reason that speculation is putting oil prices higher is the speculation of supply being interrupted and therefore the price going even higher. Iran has a missile test, oil prices shoot up. Bush removes the executive order banning offshore drilling (a symbolic move only), and the price shoots down. It is all about making sure the supply flow is not interrupted.
Drilling may not help out with supply in the short term, but if this had been dealt with 10 years ago, oil would be flowing out of these areas. As you said, there really isn't a supply issue at present anyway. It's about making sure there will be supply in the future.
Increasing domestic supply of oil does not mean that alternative fuel development stops, nor should it.
The concept of higher corporate taxes is a myth. Corporations don't pay taxes. They cost is passed along to the consumer and any reduced profit affects the stock holders.