Key Points
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Statistically, the Dow Jones Industrial Average, S&P 500, and Nasdaq Composite have generated outsize returns when Donald Trump is in the White House.
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This is the second-priciest stock market in history, and justifying existing valuations may prove impossible.
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Additionally, midterm elections have a way of giving Wall Street the blues.
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Despite jaw-dropping volatility at times, outsize stock market returns have been the norm with President Donald Trump in the White House. During his first non-consecutive term (Jan. 20, 2017 – Jan. 20, 2021), the time-tested Dow Jones Industrial Average (DJINDICES: ^DJI), broad-based S&P 500 (SNPINDEX: ^GSPC), and innovation-fueled Nasdaq Composite (NASDAQINDEX: ^IXIC) soared 57%, 70%, and 142%, respectively.
But expecting these good times to last may be a mistake — at least over the short run. Although the stock market tends to climb over long periods, a trio of headwinds appears set to make life challenging for the Trump bull market in the second half of 2026.
1. The second-priciest stock market in history would like a word
Arguably, the biggest issue for Wall Street is justifying the second-priciest valuation in history. The S&P 500’s Shiller Price-to-Earnings (P/E) Ratio, also known as the Cyclically Adjusted P/E Ratio (CAPE Ratio), reached as high as 42.84 in early June, which is a stone’s throw away from its all-time high of 44.19 in December 1999, mere months before the dot-com bubble burst.
Although the Shiller P/E Ratio doesn’t help identify when the music will stop on Wall Street, it does have an immaculate track record of foreshadowing eventual declines for the major indexes.
Shiller PE Ratio is now just 3.5% away from passing the Dot Com Bubble as the most expensive stock market valuation in history 🚨🚨🚨 pic.twitter.com/1ceOa3yhfs
— Barchart (@Barchart) June 1, 2026
The S&P 500’s CAPE Ratio has topped 30 on six occasions over the last 155 years, and they’ve all been eventually followed by declines of 20% or more in the Dow, S&P 500, and/or Nasdaq Composite. Premium stock valuations simply aren’t well-tolerated.
2. Trumpflation forces the Fed to act
While modest levels of inflation are perfectly normal, the Trump-led Iran war has pushed U.S. inflation to a three-year high of 4.2% in May. Even if the U.S. and Iran reach a peace deal relatively soon, the effects of four months of energy supply disruption, courtesy of the Strait of Hormuz’s closure, won’t dissipate anytime soon.
The latest Summary of Economic Projections (aka, the dot plot) from the Federal Open Market Committee (FOMC) shows that half of the 18 participating members expect interest rates to rise before the end of 2026. The CME Group‘s FedWatch Tool places a 76.5% probability of at least one rate hike by the FOMC’s Dec. 9 meeting.
Very hawkish dot plot.
Nine out of 18 officials have at least one hike this year (and six of those 9 have *multiple hikes*).
Only one person has a cut this year, and one participant (presumably Warsh) didn’t submit an SEP
The statement gets a complete writethru from top to… pic.twitter.com/KRwatpTFOP
— Nick Timiraos (@NickTimiraos) June 17, 2026
If Fed Chair Kevin Warsh and the FOMC raise interest rates to combat Trumpflation and borrowing becomes costlier, it could stymie the artificial intelligence (AI) infrastructure build-out — i.e., the driving force behind Wall Street’s historic rally.
3. The midterm blues arrive
A third and final catalyst that can upend the Trump bull market in the second half of this year is U.S. midterm elections.
There’s probably nothing that professional and everyday investors value more than predictability. The possibility of disrupting the makeup of Congress often worries Wall Street. According to data aggregated by Carson Group and published on social media platform X by its Chief Market Strategist Ryan Detrick, the S&P 500’s average peak-to-trough drawdown during midterm years is 17.5% — worse than any other year during a president’s four-year term.
Get ready to hear a lot about this, but midterm years tend to see their ultimate low later in the year and have some of the largest intra-year corrections.
The good news? Since 1950, off those lows stocks have never been lower a year later and up more than 30% on average. pic.twitter.com/WuWr8vWCJN
— Ryan Detrick, CMT (@RyanDetrick) November 16, 2025
As the election season heats up, investors’ appetite for pricey AI stocks, defense companies, and other sectors and industries that have benefited from a unified federal government over the last year and a half may dissipate.
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