A decade ago, the global financial order tilted on its axis: The stunning implosion of investment bank Lehman Brothers on Sept. 15, 2008, left no doubt that what had been considered a small fire in the subprime mortgage sector had been building undetected under the surface, and Lehman was the backdraft that turned it into an inferno.

When Lehman filed for Chapter 11 bankruptcy after last-ditch efforts to sell or save it fell through, the Dow Jones plummeted more than 4 percent in one day, and other banking heavyweights in the domino chain, many of which were already wobbly, began to fall. The global financial crisis ultimately would torch trillions of dollars in wealth — $70,000 for every single American, according to the Federal Reserve Bank of San Francisco — and send the United States spiraling into the deepest financial trough since the Great Depression.

So, we’ve learned from our mistakes — all this pain at least taught us something about investing risks, bubbles and contagion… right?

Yes and no, experts say. First, the good news. “Since that time period, the global economy is just in a much better state,” said Eric Freedman, chief investment officer at U.S. Bank Wealth Management.

Aggressive central bank interventions such as flooding markets with liquidity and dropping interest rates to record lows played a role in turning the tide, as did regulations regarding capital reserves, “stress tests,” and speculative lending.

“Lending standards have tightened significantly now,” said Lindsey Bell, an investment strategist at CFRA. “You don't have the derivative products now on mortgages and other high-risk loans in the market any longer; I think the restrictions put on banks with regard to capital are much better now. Banks have much more dry powder to deal with it in the event of another crisis,” she said.

“I also think financial services and the business of understanding companies is a cumulative practice. Markets and investors get smarter over time,” Freedman said. “Investors just understand the risk dynamics of the aggregate system a little better as well as individual companies.”

“Today’s investors are being smarter about their leverage ratios,” said Andy Smith, certified financial planner at Financial Engines. “Another trend we’ve been seeing among investors is hesitancy to spend frivolously. This is particularly a trend among older Americans… A big determinant of their feelings has to do with how close they are to retirement,” he said.

Bankers attend an emergency meeting at the London office of Lehman Brothers, in the financial district of Canary Wharf in London on Sept. 11, 2008. Kevin Coombs / Reuters file

But in some cases, having a once-bitten, twice-shy mentality has robbed ordinary Americans of the opportunity to profit from the market’s rebound, Bell said. “I think a lot of the retail investors, given the skittishness they felt in the aftermath of the financial crisis, missed a lot of the upside,” she said.

Even though lending standards are much stricter than they were a decade ago, some market observers worry that a push by President Donald Trump's administration to roll back regulations and curtail the influence of the Bureau of Consumer Financial Protection — formerly known as the Consumer Financial Protection Bureau, a regulatory body whose post-crash creation was spearheaded by Sen. Elizabeth Warren, D-Mass., — could accelerate a return to risky behavior.

“With the deregulation, perhaps some of those risks will be able to return,” Bell said.

“A lot of what those regulations were meant to address were direct behaviors that set the foundation for the systemic crash,” said Scott Astrada, director of federal advocacy for watchdog group the Center for Responsible Lending.

With fewer parameters in place, the subprime mortgage market grew enormously, often at the expense of those who had the most to lose, he said. “Once those mortgages failed, which had high probabilities, it had a pretty far-reaching impact,” he said. “That’s why it’s so concerning.”

In the wake of the financial crisis, Congress and government agencies set up important consumer protections to promote safer lending and a housing market that is more fair. Recent rollbacks to those protections and an easing in accountability for abusive lending expose consumers, communities and the markets to greater harm.

“There’s no excuse to take more risk than what’s appropriate for you just because something went up a lot.”

“Homeowners are more likely to receive loans they may not be able to afford,” said Alys Cohen, an attorney at consumer advocacy organization the National Consumer Law Center who warned that relaxing oversight could lead to predatory and discriminatory practices going unpunished in the future. “Companies overstepping legal boundaries are less likely to face significant consequences,” she said.

And while assurances of the market’s current strength should assuage regular investors’ fears for the time being, it pays to keep in mind that most people — even experts — didn’t see the crash coming.

“The biggest reason it’s hard to spot a bubble is because everybody is involved in the bubble,” said Mitchell Goldberg, president of ClientFirst Strategy.

Then, as now, the best way to insulate your portfolio from downturns is to make a long-term plan and stick with it, he said. “I think the investors who got through this market are the ones who had an investment plan going into the Great Recession. The people who understood how much risk they were taking … those are the people who were able to stick with their investments and not only recover but enjoy substantial gains.”

Despite a soaring stock market, trying to beat the system by betting you can bail out of riskier assets before they fall is almost always going to end in losses, Goldberg warned. “There’s no excuse to take more risk than what’s appropriate for you just because something went up a lot.”