Say the US gets 100x effecient with energy...

…what would the effect be in terms of lossed revenue that we would have otherwise sent overseas? Would middle eastern economies fall?

It would probably only take a 2x increase in US oil efficiency to cripple the Middle Eastern economy.

I say, go for it!

What do you mean, 100% efficient? For example, in transportation, if everybody is making round trips, 100% efficient would mean that no energy at all was used. In fact if mines at high altitude are providing products that are mostly used along the populous, low altitude coasts, 100% energy efficiency in transportation would mean that transportation was actually a source of power we could use for other purposes.

I think he means 100 times more efficient, which really amounts to the same thing: impossible. But as beowulff noted, all we really have to do is become twice as efficient. For that matter if we increased our energy efficiency by 30%, it would seriously impact the global price of oil. At that figure, we would be substantially energy-independent.

I’m guessing that the OP means 100% domestic production of energy – no need to import.

'Cause I don’t think even nuclear fusion would be 100% efficient in terms of energy contained in the fuel vs energy produced by some kind of power plant.

Whoops, I misread “100x” as “100%”.

There is another issue, though - oil is mostly used for energy, but it’s also used as stock in various manufacturing processes. Plastics and asphalt paving materials, for instance, derive partly from oil. Does the OP wonder what would happen if our usage dropped a hundredfold? Or just the energy part of it?

It would certanly cripple their oil income going forward, but if they’ve saved their money in diversified investments/businesses, won’t they still be rich and powerful?

Plus, if we got more efficient and the price of oil went way down, wouldn’t China/India/etc., just say “thank you very much” and consume at an increased rate until their demand sends the price right back up there?

You say that as if doubling our energy output using the same amount of resources is no big deal.

I never said that.

I just think it’s a worthy goal. I also think it’s achievable, but it will take lifestyle changes in the part of the American public. Vehicles that get less than 30MPG need to go. More use of public transportation. More careful trip planning (no driving to the store to get something when you are going past it tomorrow). Ride sharing.
And, of course, the eventual elimination of gasoline as a automotive fuel.