No, racism isn't a big winner in a diverse nation of immigrants and people of color. Even Trump's people know that.

In the closing days of the 2018 elections, President Trump’s political guru, Brad Parscale, rolled out a massive TV ad campaign featuring a worried suburban mom fussing over her daughter. The woman told herself that everything would be okay, because of Trump’s economy — yet the spot did not feature Trump himself.

This ad, Parscale said at the time, was targeted toward “independent voters” and “suburban mothers.”

Meanwhile, Trump was sending the military to the border, demonizing asylum seekers as criminal invaders, and attacking Democrats as socialists, with some GOP ads tying then-House candidate Alexandria Ocasio-Cortez to Nancy Pelosi. Republicans then lost more than 40 House seats, making Pelosi the speaker — to no small degree due to desertions by suburban women like the one in Trump’s own ad.

Now that Trump is continuing his racist attacks on nonwhite progressive lawmakers, this political dualism is on display once again. Trump is confidently proclaiming that these attacks will deliver victory in 2020 — which is a claim about his blue-collar white base — yet the real headwinds Trump faces are among those very same more upscale and suburban white voters.

Trump just unleashed a new tweetstorm aimed at the four nonwhite congresswomen he has been targeting, accusing them of “vile” and “hateful” and “pro-terrorist” rhetoric, and bashing the Democratic Party for refusing to take on the “Radical Left.”

Trump sees this as a winner, claiming that he cleverly forced the party to defend Ocasio-Cortez and “the Squad,” and this is “Not good for the Democrats!” Some pundits have endorsed this idea, suggesting this is the turf Trump wants 2020 fought upon.

Similarly, Trump campaign operatives tell The Post’s Jacqueline Alemanythat this is brilliant politics. One claims Trump’s attacks “reinforced in the minds of many Americans that the Democratic Party is the party of AOC and Omar."

Trump advisers made this same boast in 2018

What’s strange about this argument is that it pretends the last major national election never happened. Indeed, it’s worth recalling that Trump allies made an almost identical boast in the runup to the 2018 elections.

“I want them to talk about racism every day,” former Trump adviser Stephen K. Bannon said in August 2017. “If the left is focused on race and identity, and we go with economic nationalism, we can crush the Democrats.”

“The Democratic Party is at grave risk of completely marginalizing itself,” Trump adviser Stephen Miller said in the summer of 2018, scoffing at the party’s alleged embrace of “absolutist anti-enforcement positions,” and of “vile” MS-13 members.

In August 2017, the racial battle was over Confederate statues. In 2018, it was over caravans of asylum seekers. Now it’s over young, nonwhite lawmakers who are criticizing America, for which they are being told by the president of the United States that they should “go back” to the countries of their ancestry, even though three of them were born in the United States.

But in all these three cases, the argument is basically the same: The Democratic Party is defined by a race-obsessed fringe, which means it can’t win a national majority. In the Bannon-Miller mythology, a silent majority agrees with Trump on immigration and is repelled by Democratic race-baiting, and a nationalism that fuses this cultural message with Trump’s economic agenda will durably hold that majority.

But, as the ad featuring the worried suburban woman showed, even some of Trump’s own advisers didn’t believe this. They needed to decouple the economy from Trump and his nationalism and nativism, to win back independents and suburban women.

But it was too late. David Drucker reported that even Republicans privately admitted Trump’s immigration focus — his hate and nativism — helped cost the GOP the House by alienating those constituencies.

Given this history, why would anyone credulously accept Trump’s spin that similar race-baiting will be a huge winner this time around?