The insurmountable problem the US shale oil industry faces is that it is too highly dependent on debt and too reliant on crude trading above $60 per barrel to remain profitable. Break-even prices in America’s most productive areas, such as the Eagle Ford and Bakken, are thought to range from $54 to almost $70 a barrel, which currently means producers are operating at a loss, living in hope that Opec finally relents and cuts production.

In these circumstances the only thing keeping many US drillers afloat is debt, which up until now has been cheap and plentiful.

According to the data provider Factset, the amount of debt held by US oil and gas producers has ballooned to almost $170bn (£111bn) this year, compared with $81bn five years ago. But the cost of servicing that debt has also increased exponentially after a number of operators saw their ratings reduced to junk.

Opec now only has to maintain its fragile cohesion and push a little harder for the entire shale oil industry in the US to fold.

However, the group of 12 mainly Middle Eastern oil producers is itself feeling the pain of lower oil prices. Its wealthiest members, such as Saudi Arabia, the United Arab Emirates and Kuwait, are having to fall back on their foreign currency reserves for the first time in almost 20 years to make up for the shortfall in revenues.

Poorer member countries such as Venezuela, Algeria and Nigeria are now at economic breaking point. Without vast sovereign wealth funds and an abundance of cheap oil, they are close to buckling and are demanding that Opec meets to revise its current strategy.

Although Opec’s secretary general has called for a meeting of oil experts in Vienna later this month, it is extremely unlikely that ministers from the group will gather before their next scheduled date in December. Meanwhile, Saudi Arabia has continued to pump at record rates above 10.5m bpd, a strategy which is making a mockery of Opec’s overall production ceiling of 30.5m bpd.

And then there is Iran and Iraq. Combined, these close political allies in the Middle East pose the biggest challenge to Saudi Arabia’s dominance of Opec. However, both countries desperately need higher oil prices to help shore up their battered economies.

Baghdad has compensated for falling oil prices by pumping more crude. The second largest producer in Opec is now pumping around 4m bpd of crude to replenish its dwindling foreign currency reserves, which have fallen by around 20pc this year.

Iran is also champing at the bit to increase production – with the end in sight for its economic isolation from the rest of the world. According to the Iranian government, the country could increase oil production by around 500,000 barrels per day within a few months of economic sanctions being fully lifted. The Islamic republic is already laying the foundations for a return of international oil companies, which could help to boost output.

Top oil official Seyed Mehdi Hosseini told a room packed with Western executives at the Oil and Money conference that Tehran was ready to offer 50 new projects to international investors. Any significant increase in Iranian oil supply would add to the current oversupply in markets, pushing prices even lower.

Of course, there are risks. Geopolitical issues are once again acting to put a floor under oil prices. Russia’s deployment of military forces in Syria has raised the temperature in the region to boiling point. Oil has ticked back above $50 per barrel following the move, which has emboldened Bashar al-Assad.

Russia’s involvement in Syria gives Vladimir Putin a foothold within easy reach of the world’s major oil supplies and threatens the influence of Gulf states such as Saudi Arabia which are funding opposition groups not linked to Islamic State in Syria. Meanwhile, Riyadh and its Arab allies are also fighting a bitter and increasingly intractable conflict in Yemen against Iranian-backed rebels.

Russia has also suffered from the decline in oil prices, and the smouldering embers of instability in the Middle East could still result in oil prices skyrocketing if a wider conflict between Iran and the Arab Gulf states is ignited.

Faced with Russia’s vast military power and the reluctance of the US to get involved, Saudi Arabia’s only weapon against the Kremlin is to maintain lower oil prices.

Saudi officials have held high-level meetings with Russia in recent months, as have the Iranians; but Moscow’s true long-term intentions in the Middle East remain uncertain beyond simply pushing up the price of crude.

That could help US shale drillers – but not enough to prevent the industry in North America from being pushed over the edge.