Yes, it may be.
First, you have to consider all that "nationality" means, though. These are definitions of "nationality" on dictionary.com:
nationality
noun
- the status of belonging to a particular nation, whether by birth or naturalization: the nationality of an immigrant.
- the relationship of property, holdings, etc., to a particular nation, or to one or more of its members: the nationality of a ship.
- nationalism.
- existence as a distinct nation; national independence: a small colony that has just achieved nationality.
- a nation or people: the nationalities of the Americas.
- a national quality or character: Nationalities tend to submerge and disappear in a metropolis.
That's a wide array. A person's "nationality" is not as simple as what country they were born in, which it is often oversimplified as, especially in the US because of how anyone born in the US is a citizen of the US and so a member of the nation that is the United States of America. But it's not that simple, actually not even in the US, like Native Americans born in the US, if they get a passport, have a US passport showing them being US citizens, their nationality being "American," but they are also of their Native American nations, so, for example, a Chippewa's passport may show their nationality as "American," but their nationality is also "Chippewa," they being of the Chippewa nation.
Moreover, much of the world does not determine "nationality" by simply being born within a given country's borders, like German "nationality" is determined by being born to German parents, either in Germany or abroad, whereas simply being born within the borders of the nation that is Germany does not make one's nationality German such that people born within the borders of Germany to non-Germans don't have German "nationality," meaning they aren't born citizens and aren't even eligible for a German passport, much less one that states their "nationality" is "German."
Once you consider all that "nationality" may mean, you must then consider all that "race" may mean. These are definitions of "race" on dictionary.com:
race
noun
- a group of persons related by common descent or heredity.
- a population so related.
- Anthropology
- (no longer in technical use) any of the traditional divisions of humankind, the commonest being the Caucasian, Mongoloid, and Negro,
characterized by supposedly distinctive and universal physical
characteristics.
- an arbitrary classification of modern humans, sometimes, especially formerly, based on any or a combination of various physical
characteristics, as skin color, facial form, or eye shape, and now
frequently based on such genetic markers as blood groups.
- a socially constructed category of identification based on physical characteristics, ancestry, historical affiliation, or shared
culture: Her parents wanted her to marry within her race.
- a human population partially isolated reproductively from other populations, whose members share a greater degree of physical and
genetic similarity with one another than with other humans.
- a group of tribes or peoples forming an ethnic lineage: the Slavic race.
- any people united by common history, language, cultural traits, etc.: the Dutch race.
- the human race or family; humankind: Nuclear weapons pose a threat to the race.
- Zoology. a variety; subspecies.
- a natural kind of living creature: the race of fishes.
- any group, class, or kind, especially of persons: Journalists are an interesting race.
Notice the three definitions above that I've put in bold for you. Each of those three definitions allow for one's "nationality" to be one's "race," or rather for one's "race" to be based on or determined by one's "nationality."
The second "Anthropology" definition above defines "race" as "an arbitrary classification." The classification being "arbitrary" means that it can be applied to classify people by something as arbitrary as their nationality. Keep in mind that everything from "sometimes" on is just providing some examples, not a comprehensive list of every possible arbitrary classification that "race" can include.
The third "Anthropological" definition above defines "race" as "a socially constructed category of identifications based on physical characteristics, ancestry, historical affiliation, or shared culture." For one, being "socially constructed" means it's based on whatever assumptions a society or group makes, the definition of "social construct" being "a complex concept or practice shared by a society or group, not arising from any natural or innate source but built on the assumptions upheld, usually tacitly, by its members," so if any society bases "race" on "nationality" (e.g., a society of Germans in Nazi Germany basing race on nationality when referring to "The German Race"), then being prejudiced against people on the basis of nationality becomes "racist," like it was in Nazi Germany. For two, since the definition uses "or," not "and," and since "nationality" easily falls under the umbrella of "historical affiliation" and also of "shared culture," just one of those being enough, "race" can be based on "nationality," this provides two more paths by which holding prejudice against people because of their nationality may be considered "racist."
The fifth definition of "race" above, like the third "Anthropology" definition, also clearly allows for nationality to be the basis of racial categorization, thus holding prejudice against a people because of their nationality may be considered "racist" under this definition, as well, the very example given being "the Dutch race."
Now consider the following quote:
"Race is the child of racism; not the father." -Ta-Nehisi Coates
That pithy observation flows from and points to "race" being defined as "an arbitrary classification" and "socially constructed," making race both totally subjective and totally artificial, as in not bona fide, not real. What is real is racism, objectively so, because while people's assumptions and bases for categorizing other people in such a manner as race are totally arbitrary and made up, often even indefinable, even among themselves, people's racist attitudes and actions (i.e., prejudice people hold) that result are not but are quite real and become quite systematic, even systematized.
Example:
Say that my second toe happens to be my longest toe. Say that I find a bunch of
other people whose second toe is their longest toe. Say that we, now a group or society,
undertake alienating people from ourselves who are different, people whose second toe isn't their
longest toe, people we, on a basis so arbitrary as toe length, start
making disparaging assumptions about, even categorically mistreating, including those who for whatever reason seem to us like a kind whose second toe would be the longest even though we don't really know for sure, like maybe we've never seen their feet but we come to assume everyone whose toe isn't the longest smells a certain way or is left-handed or is stingy or whatever.
Then I, along with that bunch of other people who were born with their second toe as their longest toe that I've joined up with, are "racist," arbitrarily imagining a
Second-Toe's-the-Longest race exists, along with a First-Toe's-the-Longest race and other races too, like maybe one for those where neither toe
is longer than the other, they being the same size, or where the third
toe is the longest, etc., all those races being the children of my
racism, of our racism. I would have a pathology of racism, which consists of, one, using an arbitrary
basis to identify and categorize people as being born into a group that I believe includes
me and that I also include myself in and, two, in turn using that same arbitrary basis to identify and categorize people as being born into a group or groups that I believe exclude me and that I then exclude with
prejudice. So, even though there's really no such thing as a
Second-Toe's-the-Longest race, except in my imagination and the imaginations of those who've joined me, there now really is such thing
as a Second-Toe's-the-Longest racist (e.g., me). Even though I and my fellow Second-Toe's the Longest racists (believing we are superior, the Master Second-Toe's-the-Longest Race, as it were)
hold our prejudices against First-Toe's-the-Longest people,
mistreating them and whatnot with our racism, our race isn't real. Our being racist is real. Our racism is real. But our race isn't real. It's not real for a number of reasons, the most salient being that race itself's not real but just a phony, made-up, arbitrary basis that racists use to raise themselves up and benefit themselves with inclusion by putting others down and prejudicing them with exclusion, exclusion to such extent that it may even be so extreme as to include exclusion from life, annihilation.
To address what's real, people being "racist," requires addressing what's unreal, "race," the arbitrary and artificial construct racists use to categorically alienate and prejudice groups of people they call others, which being arbitrary and artificial can be anything since race exists only in the eye of the racist beholder. Therefore, if in a person's eye race is beheld as one's nationality, then prejudices that person holds against people because of their nationality would be considered racist, and that has very, very often been the case, a perfect example being:
The Yugoslav wars when those born in the nation of Serbia believed in
a Serbian race and those from the other side of an arbitrarily line
drawn in the sand in Croatia were of a Croatian race that was
inferior, even subhuman, and so pollutant that they needed to be
genocided, all wiped off the face of the Earth, despite their being
absolutely zero genotypical or phenotypical differences between those
of the so-called "Serbian" race and those of the so-called "Croatian"
race, meaning they not had no discernable physical features that made
them different from one another but didn't even have any genetic
differences that did, the two groups even speaking the same language,
nationality being the sole basis of their racism, the war and the attempted genocide of Croatians being born entirely out of prejudices
people held against people because of their nationality, which very
much was considered racist by the whole world, including by the
Serbian racists who were committing these atrocities and were quite
proud of it, because that's exactly what it was: racsist.
Therefore, it is an undeniable fact, even a historical fact, that a person who holds prejudices against people because of their nationality may be considered racist.