For years, Thomas Lee has been known as one of Wall Street's biggest bulls, finding optimism in the market where others often saw obstacles. But that's all changing now, due in large part to fears about what will happen when Donald Trump takes office at the end of next week.
In fact, Lee believes the first half of 2017 will see the market slide from its current record perch, then rally just enough to get back to unchanged when the final closing bell rings.
The year will begin, according to an analysis from the head of research at Fundstrat, with policy confusion amid a flattening yield curve in long-term bonds. That could cause a 5 percent to 7 percent drop in the S&P 500.
Lee's first-half price target is 2,150, with the year-end number at 2,275.
"Is the first half of the year a great time to be buying stocks? I think you'll get a better entry point," Lee said on CNBC's "Squawk Box." "
In a report for clients, Lee expressed worries that Trump's presidential term could see "a sloppy White House organization (that) creates confusion on U.S. policy, particularly as tweets become policy." He thinks much-anticipated fiscal stimulus may not become reality, and even insinuated that Trump will "fire" Fed Chair Janet Yellen, even though the president lacks the authority to remove central bank officials. Her term runs through February 2018.