Trump's approval rating. (Gallup)

President Trump is not the first president to see his approval rating drop to 35 percent, as it did in Gallup's most recent tracking poll.

But he is the first president on record to go that low without it owing to one of three things: war, Watergate or economic strife.

Gallup noted Monday that most post-World War II presidents had indeed sunk as low as Trump at one point or another. Ronald Reagan and Lyndon B. Johnson bottomed out at 35 percent (where Trump is already), George H.W. Bush at 29 percent, Jimmy Carter at 28 percent, George W. Bush at 25 percent, Richard Nixon at 24 percent and Harry Truman at 22 percent.

So I wondered, what prompted each of these presidents to plummet to their Trumpian lows? The answers show what an entirely different situation Trump is in.

A brief recap of what preceded their drops to 35 and below:

George W. Bush (April 2006)

George H.W. Bush (July 1992)

  • Unemployment spiked to 7.8 percent that month — the highest of any point between 1984 and 2009.

Ronald Reagan (January 1983)

  • Unemployment spiked to 10.8 percent the preceding month, marking the worst economic recession since the Great Depression.

Jimmy Carter (May 1979)

  • Inflation climbed into the double digits, after having hit 9 percent in 1978.
  • The Iranian Revolution led to a decline in the global oil supply and concerns about a possible repeat of the energy crisis of the early 1970s.
  • The nuclear accident at Three Mile Island occurred less than two months ago, on March 28, further stoking panic. The unrest would soon lead Carter to give what has come to be known as his "malaise” speech, in July.

Richard Nixon (August 1973)

Lyndon B. Johnson (August 1968)

  • For the first time, a majority — 53 percent — regarded the Vietnam War as a mistake by this point, per Gallup. And the Tet Offensive, which was launched early that year, had become a defining moment in an unpopular war.
  • Johnson announced he wouldn't seek reelection in March.
(Gallup)

Harry Truman (September 1946)

  • The end of World War II brought economic uncertainty, a sharp cost-of-living increase thanks to the end of price controls, a wave of major labor strikes, and shortages — most notably when it came to meat, which doubled in price over a two-week period.

Trump is the exception to this list in many ways. The economy is relatively strong and getting stronger, there is no big war looming, and while Democrats say his administration is already in the midst of a Watergate-esque scandal, we have yet to see anything close to the smoking guns we saw when Nixon's popularity plummeted in the early 1970s.

For the first time since World War II, we have an embattled president without a battle.