Mainstream coverage of the debate over President Donald Trump’s DACA hostage-taking has been marked by an alarming insouciance, verging on denial, about what’s actually going on — and about just how much is on the line.

Trump and his restrictionist supporters are frank about what they want, and why, but the media is often too genteel or too cowed by fear of the charge of bias to faithfully relate what newly energized ethnonationalist populists themselves say.

That needs to stop. We need to square up to the fight at hand. We aren’t having a technocratic disagreement about the optimal number of or distribution of visas. We’re having a fight about national identity, about what it means to be an American, about who counts as one of us, and about who should receive full and equal protection under the law.

And one side, led by the president of the United States, is fighting dirty, holding a sword over the necks of 700,000 young immigrants who grew up in this country.

To cast the DACA immigration debate as something other than 100-proof cultural identity politics sows confusion, obscures the urgency of our duty to protect vulnerable Americans, and strengthens the hand of the side that knows what it’s doing.

Mexican immigration — of all sorts — is a threat to the ethnonationalist vision

DREAMers come from all over, but nearly 80 percent of them were born in Mexico. For the ethnonationalist populists, immigration — and Mexican immigration in particular — is a threat to authentic American national identity, which in their eyes is white and European in origin. The American immigration policy status quo is therefore an existential threat to the nation, as the ethnonationalists imagine it. It follows that the large majority of Americans who support current levels of immigration, or higher levels, has aligned itself directly against the true national interest.

To the ethnonationalists, this capitulation to the inevitability of demographic takeover is tantamount to treason, making it an urgent matter of national self-defense to stymie the majority’s will. In making that judgment, the populists redefine “the people” to exclude practically everyone on the other side of the issue.

Donald Trump, simply by having taken DREAMers hostage while insinuating repeatedly that they (and the legal immigrant communities they represent) represent a dangerous, un-American threat to the interests of real Americans, has done grave damage to social harmony and equal liberty. He has commanded the immense cultural authority of the bully pulpit to tell Americans of all stripes how they stack up in the eyes of the American state.

White Americans anxious about retaining their cultural and political dominance have been told that, yes, they are the American-est and that they matter most. Hispanic Americans get the mirror-image message: Their existence here is a problem, their origins throw a cloud of suspicion over their status as members of “the people,” and their moral/cultural claim to equality under the law is weak.

Supporters of immigration are lost in the policy weeds as the nativist right surges ahead

The nativist premise that Mexican Americans are somehow lacking in Americanness deserves to be ground into dust. Why hasn’t it been? What are we doing? Defending the emphasis on family reunification in current immigration policy is a fine and necessary exercise. Demonstrating mathematically that deporting DREAMers will put a dent in economic growth serves a purpose.

But this sort of wonkery doesn’t hit the restrictionists where they live — in their preoccupation with an exclusive, homogeneous conception of American identity. Ethnonationalists have been walking all over liberal pluralists in the debate over national identity because the champions of multicultural America are stunned by the sudden need to defend the irreproachable against the unutterable (which Trump now utters). They can’t figure out how to fight, because they thought this issue was settled.

The Americanness of Hispanic Americans ought to be indisputable. Spanish colonial culture precedes English colonial culture in North America. Coronado made it all the way to where Kansas sits today, not far from my birthplace in Independence, Missouri, in 1541. Spaniards established settlements in Florida in the 1560s. A Spanish mission was established in what is now the state of New Mexico in 1598 for the purpose of converting the indigenous peoples to Catholicism.

The English Jamestown Colony was established in 1607. The Pilgrims did not arrive at Plymouth Rock until 1620.

The standard narrative of American history begins with the establishment of English colonies on the East Coast and then follows the westward expansion of official US territory. This makes it easy to overlook that the “Mestizo” mixture of Spanish and Southwestern indigenous ancestry is older the United States, and that Mexicans inhabited US territory before it became US territory.

Until the Treaty of Guadalupe Hidalgo in 1848, the entire American Southwest, half of Colorado, and even bits of Wyoming and Kansas were literally Mexico. (Texas declared independence earlier, but Mexico didn’t recognize it.) The treaty drew the border right through the middle of a culturally coherent, economically unified trade zone and labor market. Look closely at this map:

Trump supporters who thrill to the idea of a “big, beautiful wall” on the border largely fail to grasp that the ancestors of many of the people they want to keep out have been here all along, and that people cross back and forth over the border in part because the border crossed a people.

In 1870, the first year for which census data is available, Arizona was 61 percent Hispanic. If it works its way back up to that from today’s 30 percent, it won’t have become less American. It will have become more like it was when it became American.

Before the Gold Rush, Spanish-speaking Mexicans and indigenous people outnumbered English-speaking white settlers in California by a wide margin. Today in the Golden State, where the largest population of DREAMers lives, the most common last names are Garcia, Hernandez, and Lopez and an American is as just as likely to be Hispanic as white. DREAMers aren’t like us. They are us.

Challenging the idea that Latino Americans can be truly American undercuts the very idea of America

The fact that there’s any question about affording legal status to a class of rooted young immigrants who grew up American among Americans is shameful. It’s a reflection of the disgraceful fact that so many of us are doggedly ignorant of the country we claim to revere, and deny the plain historical truth that America has always been multicultural, that Spanish colonial mestizo culture is a foundational American culture, and that many Mexican Americans have deeper roots in American soil than those of us whose European ancestors arrived rather late in the day at Ellis Island.

It makes no more sense, culturally or ethnically, to call into question the Americanness of a young woman whose mom brought her from Hermosillo to Tucson at the age of 6 than it does to doubt that a white guy raised in Syracuse but born in Toronto can ever really belong there.

Threatening to hang DREAMers out to dry — to arrest them, to uproot them, to jail them, to rip them from their families, to sever their bonds of loyalty and love, and to cast them into exile — threatens the equality and security of tens of millions of American citizens who are ethnically and culturally identical to them.

And a threat to any subset of Americans is a threat to America — to us. Trump’s unilateral act of political hostage-taking was, from the beginning, an act of violent division, an assault on the integrity of the actual, existing, real-world American people.

The ethnically purified fantasy of the populist imagination is a seditious force that obscures our higher loyalties, shatters the peace of liberal equality, and splits Americans into warring tribes ready to abuse people whom patriotic decency would otherwise compel us to defend.

Will Wilkinson is the vice president for policy at the Niskanen Center, and a Vox columnist.

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