For the past five years investors have lived in fear of another “Lehman Moment” that would catapult financial markets into chaos.

Thanks in part to the emphatic response from the government, a repeat of that scary bankruptcy filing by Lehman Brothers in September 2008 has failed to emerge, much to the shock of economic doomsayers who warned another cataclysmic event was just around the corner.

Of course, that doesn’t mean there’s been a shortage of potential crisis-inducing shocks. Everything from Europe’s sovereign debt mess and the Japanese tsunami to the downgrade of U.S. debt and the fiscal cliff have threatened to approach, but failed to actually achieve, Lehman status.

'Worst-Case Scenario'

In the days and weeks after Lehman’s $639 billion collapse, traders spoke often about concern in the markets of “another shoe to drop,” or another catastrophic event.

“In those days people were scared to death,” Ted Weisberg, a veteran  NYSE floor trader at Seaport Securities, told FOX Business. 

Jeffrey Shafer, former undersecretary of the Treasury Department, credits regulators with preventing a second Lehman.

"There would have been more without the scale of the government response," said Shafer, who is the author of a new report by McGraw Hill Financial Global Institute about the crisis. "Although there are individual shocks, the level of fragility in the system has been reduced."

The intense worry about a Lehman repeat highlights the traumatic effect of the original event, which set off the meltdown on Wall Street that required trillions of dollars of government support to fix.

“There was systemic risk with Lehman. If you can’t trust one of your counterparties, you wonder who you can trust."

- Alec Young of S&P Capital IQ

The fallout from the collapse of 158-year-old Lehman, then the country’s fourth-largest investment bank, forced investors to realize just how frighteningly interconnected the system truly is.

“This is a worst-case scenario,” Art Hogan, then a market strategist at Jefferies & Co., told FOX Business the day after Lehman filed for bankruptcy.

The Dow Industrials plummeted 504 points, or 4.42%, after Lehman’s implosion, their worst beating since the aftermath of the September 11 terrorist attacks.

No Major Bank Failures

There were certainly a number of shocks that followed the Lehman collapse, though none of them had nearly the same ripple effects.

Just weeks after Lehman’s demise, the U.S. House of Representatives voted down Hank Paulson’s $700 billion TARP plan. While the Dow Industrials took a 778-point, or 7%, nosedive that day in response to that vote, lawmakers quickly reversed themselves and approved the plan just days later.

Thanks largely to the cash infusions lenders received from TARP and help from the Fed, there haven’t been any major failures of investment banks since Lehman.

The closest one came in November 2011 when bad bets on European sovereign debt and overleverage led to the downfall of MF Global. But the size of that brokerage, run by former Goldman Sachs (GS) exec Jon Corzine, paled in comparison with Lehman.

“There was systemic risk with Lehman. If you can’t trust one of your counterparties, you wonder who you can trust,” said Alec Young, global equity strategist at S&P Capital IQ.

Europe's sovereign debt crisis has been a thorn in the side of investors for much of the past three years. Despite concerns about the exit of a eurozone member such as Cyprus or Greece, the currency union remains intact and Europe's economy is finally rebounding.

Debt Ceiling Clashes

Some feared the May 2010 flash crash could be another Lehman moment. But the markets bottomed in just days after that scary crash, which caused the blue chips to nosedive 1,000 points in just minutes before quickly rebounding.

“The flash crash was a joke. It was a blip,” said Young.

Likewise, Wall Street managed to avoid panic after the earthquake and tsunami that rocked Japan in March 2011. That natural disaster slowed global growth, but wasn’t enough to rock investor confidence.

Stocks took just a brief detour from their years-long rise after Standard & Poor’s took the unprecedented step of downgrading the U.S. credit rating in August 2011, signaling concern about the ability of Washington to continue to function amid the debt-ceiling debate.

If there’s a candidate in the near term to be a new Lehman Moment it would be this fall’s upcoming battle on raising the $16.7 trillion debt ceiling. Failure to do so could spark a crisis and an historic default on U.S. debt. 

“It's a looming crisis with no clear end-game and a bizarre view among players in both parties that a crisis could help them in 2014,” Greg Valliere, chief political strategist at Potomac Research Group, wrote in a note on Monday.

Follow Matt Egan on Twitter @MattMEgan5