Actually, nothing...and everything.

NK's fireworks display doesn't make oil harder to find or more expensive to produce, but it does give investors the jitters because of perceived increased international tensions. Whether this is justified or not is a matter of debate, but as speculators buy oil futures in an attempt to anticipate future shortages due to trouble in Asia, the price gets driven up by supply and demand.

If full scale war broke out the price would skyrocket and those investors would hit the jackpot. If the crisis were resolved tomorrow and everyone were happy with the result, those investors would take a bath since oil prices would drop, all else being equal. That last phrase is the key, because demand is now so close to supply that almost anything that happens on the world scene causes the market to react.

In short, the people who buy and sell oil for investment have a comparable effect on the price as those who produce or consume it.