When it comes to Donald Trump’s stewardship of the economy, the consensus on Wall Street these days is that the president is still snatching defeat from the jaws of victory. Trump inherited one of the strongest economic booms in U.S. history, and now presides over a record unemployment rate. And yet, instead of promoting a consistent positive message, Trump has proven himself adept only at focusing attention on his numerous blunders: the government shutdown; the inane pursuit of a $5 billion wall along the Mexican border; the rats in his administration fleeing a sinking ship; his bizarre tweets; and what lies in store for him when Robert Mueller concludes his nearly two-year investigation. Once unflappable stock markets, finally resembling the volatility of the Trump presidency, have been sinking for weeks, punctuated by some truly bizarre upward jolts.

It’s no surprise, really, that financial indicators have gone haywire. “The issues that we were willing to suspend our disbelief on have come home to roost,” one senior M&A investment banker told me, citing slowing growth in China and Trump’s ongoing trade war. “The idea that those weren’t going to impact U.S. corporate earnings is make-believe,” he said. He also cited slowing G.D.P. growth in Europe (projected at around 2 percent for 2019), slowing manufacturing growth in the U.S. and the higher cost of servicing our increasing national debt—nearly $22 trillion and rising—as three additional drags on both the economy and the markets. The stock markets, the banker explained, have finally “woken up” to the “notion that there is going to be a drip, drip, drip of bad news regarding Trump and that he will not be able to focus on growth-producing policies.”

There are a few bright spots. Corporate earnings could rise by around 8 percent, the banker predicted, and G.D.P. growth will likely remain around 2 percent—not the 3.5 percent that the economy grew in the third quarter of 2018, but “not terrible” either. He also noted that consumers still seem willing to spend, as was clear during the retail holiday season. Reality could sink in, however, when a consumer “gets her next Fidelity statement,” he said. That’s the kind of psychological development—feeling poorer and having the written statement to prove it—that can close wallets and lead to a slowing, even recessionary, economy.

Asked about Trump’s “handling” of the economy, another senior Wall Street banker seemed to find the question humorous. Was I asking a “trick question” he wondered? “If it doesn’t involve name-calling or taking credit for something”—falling oil prices, for instance—“he has nothing to do with it,” this person said. “He’s only ‘handled’ crushing any momentum he created through deregulation and tax cuts by mismanaging trade negotiations and under-investing” in the country’s infrastructure.

“By creating uncertainty, he is shutting the financial markets,” the banker continued, citing the fact that there was very little new security issuance in December, which is traditionally a slow month for such things. (Indeed, not a single U.S. company issued new high-yield debt in December, the first time that has happened in seven years.) Trump’s handling of the trade dispute with China has him worried too—despite the fact that Wall Street generally believes it is a fight worth having—since he’s not sure the conversation is “positioned properly to mitigate some (hopefully) short-term pain for long-term gain.”

He thinks it’s “still too early” to tell if all this Trump-related mishegas will result in a material slowdown in Wall Street deals, the lifeblood of the global investment-banking business. The big step down in the markets in December may have been driven as much by people being on vacation—resulting in less liquidity in the markets—than something going fundamentally bonkers. We “need a few weeks where everyone is back from holidays to really assess,” he continued. He said that while declining Apple sales in China was “not a good macro sign,” it was “offset” somewhat by the announcement of Bristol-Myers Squibb’s $74 billion acquisition of Celgene. (Wall Street likes the announcement of big mergers, as one often leads to another and there are usually big, multi-million-dollar fees paid to Wall Street advisers.)

He also is a fan of power sharing in Washington. “Government gridlock is generally good for markets,” he concluded, “and if the Fed stands down”—by not raising interest rates too often in 2019—“we might get out of this. But the ride will be bumpy.”