More than we may realize, the world has been riding a lucky streak since the global financial meltdown in 2008. How so? The years between 2008 and late 2013 were . relatively speaking . a rather benign period of big power politics and geopolitics. This allowed the major economic powers . the United States, the European Union, China, India, Russia, Brazil and Japan . to focus almost exclusively on economic rehabilitation. But now there are strong indications that our vacation from geo-instability is over.

The last time the world witnessed such a steep and sustained drop in oil prices . from 1986 to 1999 . it had some profound political consequences for oil-dependent states and those who depended on their largess. The Soviet empire collapsed; Iran elected a reformist president; Iraq invaded Kuwait; and Yasir Arafat, having lost his Soviet backer and Arab bankers, recognized Israel . to name but a few. Admittedly, other factors were involved in all these events. But, in each case, steep drops in direct or indirect oil revenues played a big role.

If today’s falloff in oil prices is sustained, we’ll also be in for a lot of surprises. Some will have happy endings. Cuba’s decision to bury the hatchet with America had to have been spurred in part by Havana’s fears of losing some or all of the 100,000 barrels of subsidized oil a day it gets from the now cash-strapped Venezuela. Others could be very destabilizing. Today’s world is much more tightly interconnected and interdependent than in the last oil price drop-off, which was before the spread of the Internet. And today’s world has so many more actors . superpowers and superempowered individuals and hackers who can destabilize companies and countries with cyberweapons. See dictionary for “Sony” and “North Korea.”When I hear President Vladimir Putin of Russia bragging that lower oil revenues won’t affect the Russian people because they are stoic . look what they tolerated in World War II . my reaction is: “Mr. Putin, that was before there was a significant urban middle class in Russia, one you helped to build with trickle-down oil and gas revenues.” A lot more Russians today have gotten used to traveling abroad, owning a car (note Moscow’s traffic jams), consuming Western goods and seeing how the rest of the world lives. Let’s see how stoic they are today. Russia’s former Finance Minister Alexei Kudrin was quoted by The Financial Times on Monday as saying, “There will be a fall in living standards. It will be painful. Protest activity will increase.”The Western sanctions on Putin’s banks, combined with the sudden sharp drop in oil prices and capital flight also triggered by the sanctions, mean that Russia has a dangerous gap between the funds flowing into its economy and what it needs to send out to pay its debts and finance its imports. Putin can’t relieve the pressure without a lifting of Western sanctions. That would require him to reverse his seizure of Crimea and intervention in Ukraine.

If Putin admits his Ukraine adventure was a mistake, he will look incredibly foolish and the long knives will be out for him in the Kremlin. If he doesn’t back down, Russians will pay a huge price. Either way, that system will be stressed with unpredictable spillovers on the global economy. Remember: Russia’s 1998 economic collapse . also triggered by low oil prices and the moratorium it declared on payments to foreign debtors . helped to sink the giant American hedge fund Long-Term Capital Management, sparking a near meltdown on Wall Street.

A prolonged drop in oil prices will impact Algeria, Iran and Arab Gulf states, where aging regimes have used high oil prices to increase government salaries to buy quiet from their people during the Arab Spring. Also, in an age when machines and software are ensuring that average is over for workers in developed countries, and everyone needs to be upgrading their skills, what happens to the developing Arab states and Iran, who have used oil money to mask their deficits in knowledge, education and women’s empowerment? Egypt’s military-led government is highly in need of Arab oil money to get through its crisis. A bit of good news: The Islamic State, which depends on oil smuggling, will fail at governing even faster than it already has.

Meanwhile, Turkey’s increasingly tyrannical president, Recep Tayyip Erdogan, who has been arresting domestic opponents, is looking like “Vladimir Putin Jr.” Erdogan is a tragic figure because he did much to build Turkey’s economy into a powerhouse. But, today, according to The Financial Times, Turkey now “needs more than $200 billion of foreign financing a year, more than a quarter of gross domestic product, to maintain its current level of growth.” There will be less Arab and Russian oil money for that and, last week, with Erdogan being criticized by the European Union (a big source of investment income) for arresting his opponents, the Turkish lira hit a low against the dollar. Watch that space.

High oil prices covered many sins and fostered many sins. If they stay low again for long, a lot of leaders will have to pay retail for their crazy politics, not wholesale. The political and geopolitical fallouts will be varied . good and bad . but fallout aplenty there will be.