Trvlr500,
What I wasn't happy about your "overpopulation" and "illegal" arguments is that I personally believe that you were pulling in blames or anger from other area of your life into the "fuel" part of your argument, which I do not see justified. Thanks for not bringing it up again.
Now regarding to why I think running out of oil is NOT a problem. I am not promoting the idea of FORCING people to live in the city. When the price go so high, eventually the housing price and living cost dynamics will change, and people will move at their own free will. Just look at it this way: homes in suburbs with new developments are better, cost more, and people want to live there and commute to work, work happens around population centers and the downtown sits empty to rot with a lot of existing infrastructure (like government, financial institutes, schools, parks, highways, roads, public transits).
Then if/when oil price goes up (say, $300/barrel due to whatever reason, like USD drop, China/India increase consumption, WW3 in the middle east, cheap oil well run dry and you have to extract oil at a cost of $200/barrel), the cost to drive the same commute goes up from $10 to $30 for a small car per day, or $20 to $60 for an SUV per day. How many people will "consider" small cars now? How many real estate developers/politicians will redevelop run down neighborhood in downtown? how many people would buy homes close to downtown? How many people will move to the suburb because they are unemployed and houses are cheap, and turn the suburb into the new slum?
No one is forcing you to do anything, if you have money, your life remains the same. However if you are like most people who don't want to spend too much on fuel, well, you will feel like changing on your own. Sure, you can't fit in a small car, maybe you'll buy a large car or a small SUV, but that's your choice at that time because you know best, but most people will be picking something that uses less fuel.
Oh, will higher density turn a city into a slum automatically? Not always. It is the people's quality that turn a place into slum. When better people move into a city because it is more convenient, it actually improves the city and drives the low income people that usually correlated to a slum out of a city.
Stockton, CA are getting all the semi-rejects from the San Francisco Bay Area because it is much cheaper to live there, and when the fuel price goes way up, the property prices in Stockton crash and people who can afford to move back into the Bay Area to reduce commuting cost, making Stockton a crime town rival Oakland and Richmond, CA.
East San Jose and East Palo Alto used to be a crime ridden down town that gets drive by shooting all the time, and as the redevelopment happens with higher income residents moving in, it transform into something that is much safer than before, at least you don't get shot in drive by shooting.
Now regarding to foreign aid. Sure you can stop all of them all together and I would love to support that if possible. However do you think we will get the cheap oil from Nigeria and Saudi if all those "bribe" were stopped? How much do you think people will be paying for oil if there are no "stability" in oil producing regions and everyone is fighting for oil with infrastructure being bombed all the time? Where do you think we will get our $30-70/barrel oil then? My point is, regardless of right or wrong, the "effect" of these foreign aids is that we in the US get a hefty discount on our "fuel" or "oil" by stabilizing the price with "foreign aid" and they are paid primarily because of this.