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You've gotten good answers, but allow me to expand with an eye towards a Cunningham's law situation. We have to address "how did all that carbon get underground in the first place?" I can't tell you much about oil, but coal is buried trees. They buried because there were not yet microorganisms that could break them down. So atmospheric carbon ended up underground due to the extraordinary circumstance of 1) there were tons of trees 2) the trees died 3) the trees could not decompose, so their carbon ended up buried then subjected to geological processes that turned them into a kind of rock. This takes the thick, CO2 and O2 rich atmosphere that gave us 3 foot wide dragonflies (which, honestly, pretty cool), and turns it into the one where we can live now. This process will never happen again, because now trees can break down.

If you wanted to zoom out and squint and get a little biblical, this is a Garden of Eden situation. There was an atmosphere that could not support our lives. There was a perfect mix of things at the same time to change that atmosphere into the one in which humans flourished. It was something too powerful we'd never be able to replicate ourselves. All we had to do was not exploit buried hydrocarbons. But we've instead made a race to dump as much carbon in the atmosphere as possible, it would seem. And now the comfortable world we live in will doom us to live outside of paradise.