Neither the violent protests that intensified over the weekend nor rising trade tensions with China could hold investors back from buying stocks Monday. They focused instead on manufacturing and construction data that suggest the economy may be beginning to recover.

Tech stocks led the advance, pushing the Nasdaq up two-thirds percent. Boeing gave the Dow ballast. The blue chip index and the S&P 500 gained over a third of a percent.

But RegentAtlantic research director Andy Kapyrin is cautious about the outlook after the market's quick snapback:

"It is hard to see that the market's next move is going to be up another 20%. But it is easy to paint a picture where news moves of a particular variety causes a 20% drop. And that is why I'm a cautious bear."

The social unrest pushed major retailers like Walmart and Target to close some of their stores, pressuring their shares.

Leading the decliners: healthcare stocks, including Pfizer and Gilead Sciences. Pfizer said its late stage trial of its breast cancer drug, Ibrance, was not likely to meet the main goal of a large-scale study while Gilead Sciences' antiviral drug remdesivir showed mixed results in a late stage study of people with moderate COVID-19.