1. I've long felt that 2012/13 was going to be a time period when something pretty serious happens. It is pretty obvious from the present megaproject data that by then, new capacity coming on line starts to fall significantly behind what is needed to replace depletion. Given present oil prices and economic conditions, it is also very likely that we are not going to be seeing a lot more megaprojects entering the pipeling in time to make much of a difference in this. SO, by around 2012, there should be a pretty substantial supply shortage, even if demand continues to be constrained.

2. Based on some of the ELM analyses that westexas has posted, it looks to me that 20 years out for zero US imports is probably about the best case (although the US might still be getting a trickle from Canada then). I'm more inclined to think that China and Japan will use their massive accumulation of US $ and treasuries to lock in long-term supply contracts, thus shutting the US out earlier rather than later. (As for the US using its military to acquire by force what it cannot acquire through legitimate commerce, that is likely to destroy as much or more supply than it will secure.)

3. The most credible scenario is sovereign default. Nations elect to exercise sovereign default only when they are so backed into a corner that the pain of sovereign default looks to be less than the pain required to honor their debts. Of course, sometimes national governments miscalculate, or just plain make bad decisions.

For the US, sovereign default would mean instant loss of reserve currency status for the US dollar, and probably also almost instant curtailment of all oil imports. Needless to say, the minute this happens, the US becomes a 3rd world economy for certain, and probably forever. Some might assume that such a thing is unthinkable and would never happen. The question is, though: are there scenarios where the burdens of continuing to honor our national debts to foreigners would be so unbearably painful that the consequences of sovereign default would start to look preferable?

To answer that question, consider whether you think that TPTB or the American public would prefer that the US FedGov continue paying interest on that portion of the national debt owed to foreigners, at the expense of:

Having to withdraw all of our military forces from overseas, even if they are in the midst of a conflict, and of having to make huge cuts in our military forces?
or

Having to make huge cuts or even eliminating altogether Social Security and Medicare obligations?

or

Having to eliminate almost all other federal government programs?

or

Having to raise federal income taxes or implement at VAT, raising the AVERAGE tax burden to 50% or more?

We are probably less than 4-8 years away - and maybe sooner - from having no choice but to face up to one of these fundamental, painful tradeoff decisions. Maybe we'll have to accept all of the above in order to keep making payments on our national debt. Are we willing to do that? At what point does sovereign default start to look not quite so painful or unthinkable after all?

Of course, once TPTB finally realize that we've only got a few more years of imports coming in any case, and once they've finally come clean with the general public about this, then a lot of the downsides of sovereign default start looking a lot less painful.

My guess is that a US sovereign default is probably not in the cards anytime before 2015, and may not be avoidable anytime much past 2025 or so.