Unless the cost of oil goes down dramatically, the only way for hypersonic flight to become affordable for the masses is for new technology to achieve drastic fuel savings. If that happens, there would be no reason to oppose it any more than one might oppose "regular" air travel today.

Commercial airlines have an extremely strong incentive to reduce carbon emissions, more so than virtually any other industry. I wouldn't worry too much about aviation tech moving in the less efficient direction.

I don't know if you are referring about my comment "fewer hydrocarbons", but it was a direct reference to the post I was referring to, "cool way to burn hydrocarbons". I wasn't trying to be pedantic or correcting anybody. Maybe I should have said less, but... I just didn't. The point is simply that higher efficiency doesn't directly equate to more usage; though it can in some cases.