Strong first-quarter financial results from Tesla and a couple of airlines couldn't save Wall Street from another sell-off in today's regular trading session. All major averages closed sharply lower, reversing early gains, with the tech-heavy NASDAQ and the Russell 2000 suffering the most significant losses.

The usual suspects behind Wall Street's selloff are anxiety over the Russia-Ukraine war and rising interest rates. For most of the trading session, the 10-year Treasury bond traded with a yield of above 2.90%, more than twice the level it traded six months ago, and closer to the psychological level of 3% and thanks to a robust economic report out of the Conference Board, which added to inflationary fears catching up with Wall Street traders and investors.

Meanwhile, comments from Fed Chairman Jerome Powell that the nation's central bank is prepared to hike interest rates faster to bring inflation under control added to the negative sentiment.

"Investors are worried by Federal Reserve chairman Jerome Powell's confirmation that the central bank will raise interest rates by 50 basis points next meeting," said Robert Ross, founder and CEO of tikstocks.

"Not only is this the first 50 basis point increase in two decades, it's also the first time we've had back-to-back rates hikes since 2006. Since higher rates slow the economy, investors are bracing for tighter monetary conditions across the board as the central bank fights the highest inflation in 40 years."

"The people close to the Federal Reserve have been publicly talking down the likelihood that measures would be taken to combat inflation," said Chris Barnes managing director of the financial services research division of Escalent. "So, when Jerome Powell indicated a half-point rate hike is "on the table" for May, there was some surprise among investors."

Still, the magnitude of the selloff when it's measured from the early gains indicates how sensitive traders and investors have been to growing domestic policy and geopolitical uncertainty.

"The market is saturated with uncertainty thanks to supply chain woes, the war in Ukraine, and ongoing concerns over inflation," said Barnes. "Introducing something even mildly unexpected to the market under these conditions - especially an interest rate hike - surely drove much of today's short-term market activity."

Nonetheless, Barnes thinks that selloffs like Thursday's trading session don't signal a downward trend.

"We have been closely monitoring sentiments among key investor groups, and while there's significant concern about the future of the market, these institutional investors will stay in the market for as long as they possibly can,” Barnes says. “With returns as low as they are on traditional savings and other similar vehicles, there's just nowhere else for them to go. They'll stay in the market until it's absolutely impossible for them to do so."

That's when either liquidity dries up and banks begin to pay meaningful returns on deposits or earnings decline significantly, prompting even long-term investors to head for the exits.

And there's the possibility of a black swan event, as sharp market reversals could catch too many investors on the wrong side of the market.