The Donald Trump presidency arouses such passion because core American national questions are often at stake. Behind the incomprehensible tweets, weird outbursts and shady operators, the <a href="https://www.thenational.ae/opinion/comment/mueller-report-when-did-the-bar-on-presidential-conduct-sink-so-low-1.851861">character</a> of the country is frequently being contested. Several crucial themes, especially the demographic and cultural nature of US society, and the role and credibility of the judiciary, are distilled in a new Supreme Court case. Last week, oral arguments were heard in Department of Commerce v New York, a lawsuit challenging a Commerce Department plan to cook the books in the upcoming census by asking if respondents are <a href="https://www.thenational.ae/opinion/comment/the-us-border-crisis-is-one-of-donald-trump-s-own-making-1.848474">US citizens</a>. That question hasn't been asked of everyone since 1950, because, as the Commerce Department’s own experts maintain, it will produce a significant undercount of roughly six to seven million people. The US Constitution calls for an "actual enumeration" of all people in the country, not just citizens, every 10 years. But, given the current climate of fear and anger regarding immigration, suddenly asking everyone this loaded question will lead many, especially Latinos, to not respond and therefore not be counted. Commerce Secretary Wilbur Ross, a noted Trumpian with, to put it gently, anti-immigrant attitudes, is insisting on adding this question precisely because he knows that will be the result. It's exactly what he wants. The thinly disguised raison d'être of the Trump administration is to champion supposedly besieged white ethnic interests. The relationship of racial and ethnic groups, and various regions, with the government in the next decade will be largely shaped by the census. If between six and seven million people, mainly of Latino origin, can be simply wiped off the books, there will be colossal repercussions. Areas of high immigration will find themselves underfunded, underserved, and disadvantaged in almost every way government operates. The congressional and other elected representation of these districts will be significantly weakened, while residents of other areas that are not undercounted will be relatively strengthened. It's instantly obvious how deeply this will advantage the Republican Party and its voter base, at the expense of the Democratic Party and its constituencies. The change will be far-reaching, fundamental and will take at least 10 years to repair. Like so much else in Mr Trump's agenda, it's a futile but damaging effort to turn back the tide of history, which is generating irreversible demographic and <a href="https://www.thenational.ae/world/the-americas/donald-trump-threatens-closure-of-us-mexico-border-1.842786">cultural changes</a> in the United States. That intention is implicit in Mr Trump’s slogan, “Make America Great Again”, which suggests that in the good old days of racial segregation, rampant discrimination and a clear white demographic majority the country was better off. But if you can't turn back history, at least you can manipulate essential data in an attempt to politically downplay and hamper the emerging new reality, which is what Mr Ross is trying to do. Several lower courts have easily seen through his clumsy pretexts, noting that his stated reasons, preposterously including protecting voting rights, are obviously false, and that his own experts don't want to do this because it cannot serve any legitimate purpose. But, judging from the oral arguments, it looks like the new five-vote Republican majority on the court is going to turn its back on traditional conservative ideals, all of which run counter to Mr Ross's legal and factual claims, and uphold his underhand scheme. If they do, they will be confirming that, for now, the high court has become as politicised and partisan as Congress. Many Americans would conclude that, despite the protestations of Chief Justice John Roberts, there are now indeed Republican and Democratic judges, and that the Republicans are determined to use the court’s power to promote the interests of their party and its largely white and non-urban constituency, if necessary by cheerfully discarding their own stated legal “principles”. Either way, this case will be a watershed in the emergence of a multi-ethnic United States. Will everyone be equally represented? Or will the court exacerbate existing constitutional distortions that have already unduly empowered a white, non-urban minority – which elected both Mr Trump and the Republican Senate – at the expense of a cosmopolitan, urban majority? Under Mr Trump, the Republican Party has positioned itself as the defender of this unjust ethnic and geographical privileging and seeks all means, even including deliberately distorting the census count, to protect it. If they allow that, many Americans will despair that this Supreme Court can be an impartial arbiter, capable of fair rulings when Republican interests are at stake. Many will view the new conservative Supreme Court majority – partly created through outrageous chicanery and shenanigans, such as the Republican Senate’s refusal to grant Barack Obama's nominee, Merrick Garland, a hearing, let alone a vote – as just another gang of unscrupulous GOP apparatchiks. The census can't be revisited for a decade. But the court can. And if the Supreme Court persists in a shamelessly partisan turn, it probably will. Congress could simply expand the number of justices from nine to 13, or any number it likes. Republicans would angrily denounce this as illegitimate "court packing". But many Democrats would counter that “court-balancing” is not only warranted but essential to salvage American democracy. <em>Hussein Ibish is a senior resident scholar at the Arab Gulf States Institute in Washington</em>