Gas got cheap because of the development of a new technology in the seventies, bright spot seismic. Pressure waves and shear waves are affected differently by passing through fluids, so you could directly detect oils or especially gases. This trashed the price of natural gas for a generation.
Now we know that the easy gas is gone. Tight sands, arctic, off shore, tight shale, coal bed methane, etc, are pretty much what's left.
Ahhhh . . . then that is a problem. Bright Spot Seismic, huh? That's some pretty cool stuff.

It seems like the more I think about this, the more I start tilting in the nuclear option. There's obviously a lot that needs to be done in terms of re-ordering of our way of life to make it less energy intensive, but the nice thing about Nuclear is that it does appear to be a stable source of energy if you start using breeder reactors and recycle your waste until the point of close to net energy extraction.

But I'm hardly an expert.