President Trump’s tweets calling on four Democratic congresswomen of color to “go back” to the “corrupt” countries they came from sparked the controversy he undoubtedly wanted, as did his subsequent attack on one, Representative Ilhan Omar, a Democrat from Minnesota.

The chant “Send her back,” a variation on the 2016 Trump supporters’ chant about Hillary Clinton, “Lock her up,” resounded through a recent political rally.

These slights reveal Trump’s fondness for a rhetorical device called synecdoche.

Difficult to pronounce but easy to define, synecdoche comes from the Greek synekdokhe, which means “an understanding one with another.” It substitutes a part for the whole, using that one part to represent the whole.

The title of the television series “Suits,” in which formal clothes represent scheming lawyers, nicely illustrates the idea. When people say “wheels” for cars, “boots on the ground” for occupying soldiers or “Ol’ Blue Eyes” for Frank Sinatra, they’re using synecdoche.

In the president’s case, he wants to make “The Squad” represent the Democratic Party. Trump thinks his chances for reelection will improve if people see these four women every time they hear the word “Democrat.”

FDR gets away with it

If Trump’s use of this strategy feels familiar, that’s because synecdoche happens during every election. I notice these things, because I’m a scholar of political rhetoric.

Presidential candidates are themselves synecdoche. They represent their whole party. If they’re popular enough, they create what’s called a “coattail effect.” People vote for the entire party because of one person, its leader. The reverse can be true as well: A poor candidate, like Republican Barry Goldwater in 1964, can drag down the entire party.

In 2018, Democrats sought to attach the president to every single Republican in a swing district, while Republicans demonized House Speaker Nancy Pelosi as a way to tarnish all Democrats.

Trump’s tweets twist the usual strategy by aiming his synecdoche at House members. This is rare for a president.

One prior example is Franklin Roosevelt’s 1940 reelection campaign. Seeking an unprecedented third term as war raged in Europe and Asia, Roosevelt, a Democrat, faced a formidable opponent in businessman Wendell Willkie.

New to electoral politics and an outsider, Willkie exuded charisma. He criticized Roosevelt’s economic record, but shared his concern for national defense. Unlike many Republicans of the era, Willkie was no isolationist.

Roosevelt did not want to attack Willkie; the president admired the Republican liberal. Instead, he found his Republican foils in the the crusty old House minority leader, Joseph Martin; in Bruce Barton, an advertising executive turned politician; and in Hamilton Fish III, a strident, conservative isolationist.

“Martin, Barton and Fish” – the chant became a staple at FDR’s campaign rallies, as he detailed their opposition to every New Deal reform and national defense measure. When FDR got away with that synecdoche, Willkie later said, “I knew I was licked.”

Democratic nominee becomes irrelevant

Roosevelt could control the political narrative because, as president of the United States, he was the nation’s chief storyteller, the keeper of national myths.

That’s the power of the president. Because of it, presidents can influence perceptions of political reality. This is what Trump is attempting to do as he enters the 2020 presidential campaign.

He wants to define the Democratic Party to his advantage. And, as David Brooks recently wrote in The New York Times, the president has a “vested interest in keeping the progressives atop the Democratic Party.”

If these four women represent Democrats – much as a representative serves as a proxy in Congress – then Trump’s synecdoche suggests that the Democrats are only these progressive women of color.

By identifying his opponents as the party of leftists, women and minorities, Trump thinks he can secure crucial white working-class votes.

If this strategy works, the Democratic nominee in the 2020 election becomes irrelevant. That leader, like Willkie, would no longer be the face of the party.

The president’s personal lawyer, Rudolph Giuliani, explained this strategy after Trump’s attack on Maryland Democratic Congressman Elijah Cummings.

“Whenever the members of Congress like [Rashida] Tlaib or [Alexandra Ocasio-Cortez] or Cummings are the focus, that means the focus is not on [Kamala] Harris or Joe Biden. Every time people go crazy, it’s still cemented in some people’s minds that these people are maybe the modern Democratic Party,” Giuliani told the Washington Post.

As Richard Nixon did with his divisive “Southern Strategy” in 1968 that exploited white racial animus in the South, Trump’s “Squad Strategy” offers the promise of victory through polarization of the electorate. “They” are not like “us.”

Could it backfire?

Yet 2020 is not 1940 or 1968. Heightening racial tensions with synecdoche is now a risky choice.

For one thing, the nation no longer looks like it did in 1968. The white working-class part of the electorate has been shrinking. More people identify with the Squad than ever before.

By attacking representatives Ocasio Cortez, Omar, Pressley and Tlaib, Trump may encourage women, minorities and those who like this foursome to head to the polls.

As important, an incumbent president’s greatest advantage is, well, incumbency. Only 10 U.S. presidents have failed to win reelection, because the office itself and people’s respect for it is a significant electoral advantage.

But if President Trump squanders that respect through racially divisive strategies like his attacks on the Squad, Representative Cummings and Baltimore, it could cost him in 2020.

Americans may no longer see Trump as a part for the nation’s whole.

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