This is not entirely correct. If the world geopolitical stance went against the U.S., this would not mean the end of oil. It would mean the end of the USD, and another reserve currency will take its place. Oil is just another commodity, and it is only under the tyranny of the U.S. due to its global dominance. One day, this might not be the case.
This is exactly correct. I see this misconception about USD a lot. USD is backed by commodities plus military strength. The U.S. is years ahead every other country in military R&D, with China being behind them, and that puts high value on USD for stability reasons. It's why oil prices can collapse and USD can still main resilient. The U.S. economy can have trouble and it still won't send people running away from USD entirely.
Venezuela's currency is entirely backed by oil, and when oil crashed, so did their economy. You cannot merely have a currency built upon a commodity.
Exactly. Military strength and fear too..
People wonder why the U.S. were the first to start nuclear bomb testing, or why so many nuclear bombs have been created (and dropped) to date. The reason is simple, power and fear. All of that drives the usage of the USD, so that countries fear their reign and fear building an economy outside of the U S. More military power = more fear of countries subservient to the U.S. (this principle also applies to other super powers of course, except the U.S. is likely to be the seed).
It's sad, however it's the truth. Currently, currency isn't backed at all by love but backed by fear. Fear of military threat, fear of impossible survival, fear of tyranny. "In god we trust"? It should be, "In fear we obey".