Behind the sturm und drang that greeted President Trump’s recent executive action on refugees lies the broader issue of U.S. immigration policies over the past half-century. And behind those immigration policies lies a profound question facing Americans: what kind of country do they want their country to be?

For most of our history, we have been largely a country of Europeans, a country of the West, with Western sensibilities and a shared devotion to the Western heritage. Now we are in the process of becoming something else—a mixed country without a coherent, guiding heritage of any civilization and certainly not of the West.

This is largely the result both of the numbers of immigrants coming into the country (both legal and illegal) and of the place of origin of most of those immigrants. In 1960, 84 percent of U.S. immigrants came from Europe and Canada; now that number is just 14 percent. Also, the percentage of people in America who were born outside the United States reached 13.7 percent in 2015—just a shade below the all-time high for that statistic, which was 14.8 percent in 1890, after a similar wave of immigrants largely from Central and Eastern Europe.

What’s more, experts expect that percentage to climb to 14.9 percent by 2015 and 18 percent by 2065. In 1965, when the country’s current immigration philosophy was enacted into law, the percentage of foreign-born people in the country was 5 percent. According to the Pew Research Center, by 2055 the United States will have no ethno-racial majority. When that happens, America will be a completely different country from what it was, say, when the Baby Boomers appeared on the scene and throughout American history before that.

This is a profound national alteration, and what’s remarkable about it is how little debate, or even discussion, has attended it until recently. The American left and most of the country’s elites considered it a natural and beneficial development, a testament to the value of diversity and a shared aversion to discriminatory practice or even discriminatory thinking. Any suggestion that this sweeping change in the makeup of the American population could be ultimately detrimental was considered an assault on the country’s core values and hence our foundations. That tended to stifle dissent. And, if wary critics got too uppity, there was always the allegation of racism to shut them up.

Then came Donald Trump, whose crude pronouncements on immigration heralded that this was one politician who wasn’t going to be silenced or intimidated on the issue. Whereas the nation’s political class had settled upon a strategy of finessing the issue of the 11 million or so illegal immigrants in the country, which meant keeping it out of the presidential campaign so it could be handled later in a more manageable legislative setting, Trump forced the issue to the forefront by saying they should all leave the country.

They won’t, but Trump likely will succeed in deporting criminal elements within that number and in diminishing the inflow of illegal immigrants significantly. The issue has been joined, and it will be decided in the political arena, in full view and in full cry. It won’t be finessed by a stealthy Congress.

It’s in that context that we should view the emotional political byplay unleashed by Trump’s executive order that temporarily banned travel into the United States from seven Muslim-majority countries, suspended refugee admissions for four months, and barred Syrian refugees indefinitely. The issue is being joined largely as a security issue, and in large measure it is. But the arguments, pro and con, that greeted the president’s action are essentially the same arguments that will attend the broader immigration issue as it unfolds.

Opponents view the action as illegal and unconstitutional, but also fall back inevitably to the argument that these discriminatory policies undermine the country’s core values and foundations. “This is not who we are,” as Obama put it repeatedly during his tenure as president. The idea of constrictions on the inflow of refugees or immigrants grates on these people.

Defenders of the Trump action, meanwhile, argue that nobody outside the United States has any rights with regard to entering the United States, and hence discriminatory actions in letting people in, or not, have nothing to do with American values. They believe also that the U.S. government and American people have every right to determine what inflows and what restrictions on inflows they want to accept or deny—for whatever reason but particularly for security reasons.

After all, U.S. refugee policy has fluctuated significantly over time, with numbers in excess of 110,000 in some years and as little as 27,000 in others (particularly following the 9/11 terrorist attacks on American soil). President Obama sought to get that number up to near its apogee in 2017, but Trump wants to cut it to 50,000. How, Trump’s defenders ask, does that undermine American values any more than they were undermined when the refugee number was 27,000?

And so we see that ultimately this debate—whether focused on refugees or the broader immigration issue—is about numbers. Anti-Trump liberals want more immigrants, particularly if they are not Europeans. They want that percentage number on foreign-born Americans to go up, beyond the 2015 number of 13.7 percent, beyond the 1890 record of 14.8 percent, and shooting for the projected 18 percent. The day that there is no longer a European majority in America is welcomed by them—the sooner, the better.

Trump supporters want fewer immigrants to allow the country to better absorb that current 13.7 percent of foreign-born Americans, to allow for some debate about the implications of current immigration policy, and to preserve the country’s ties to the Western heritage.

This is a debate about the definition of America, and definitional debates are not easily adjudicated. The emotions unleashed by Trump’s recent executive action are just the beginning.

Robert W. Merry, longtime Washington, D.C., journalist and publishing executive, is editor of The American Conservative. His next book, due out from Simon & Schuster in September, is a biography of William McKinley.