By then we will have the technology to make cars that run on water and that will be our main source of income.
I'm not saying that our coal supply is limitless, and I'm not saying America will be long gone before its gone, but what I'd like to point out is our current technology still supports gas guzzling cars, and we do need to let the technology get further ahead before we can claim our independence from gas, coal, and ruining the earth. Coal happens to be able to sustain an independent good economy while that happens. We need an intermediate step before we get off all petroleum and what not.
But if people are allways thinking in the same way that you are thinking, then we WONT have the technology!