U.S. President-elect Donald Trump walks onto a balcony at the Capitol building. (Nicholas Kamm/Agence France-Presse/Getty Images)

Robert D. Kaplan is a senior fellow at the Center for a New American Security and author of “Earning the Rockies: How Geography Shapes America’s Role in the World,” to be published in January.

President-elect Donald Trump is being called a “realist” in foreign policy. Don’t believe it. He may have some crude realist instincts, but that only makes him a terrible messenger for realism. Realists like myself should be very nervous about his election.

Realism is a sensibility, not a specific guide to what to do in each crisis. And it is a sensibility rooted in a mature sense of the tragic — of all the things that can go wrong in foreign policy, so that caution and a knowledge of history are embedded in the realist mindset. Realism has been with us at least since Thucydides wrote “The Peloponnesian War” in the 5th century B.C., in which he defined human nature as driven by fear (phobos), self-interest (kerdos) and honor (doxa). Because the realist knows that he must work with such elemental forces rather than against them, he also knows, for example, that order comes before freedom and interests come before values. After all, without order there is no freedom for anybody, and without interests a state has no incentive to project its values.

Trump has given no indication that he has thought about any of this. He appears to have no sense of history and therefore no mature sense of the tragic. A sense of history comes mainly from reading. That’s how we know in the first place about such things as our obligations to allies and our role as the defender of the West. All previous presidents in modern times, without being intellectuals, have been readers to some extent. But Trump seems post-literate, a man who has made an end run around books directly to the digital age, where nothing is vetted, context is absent and lies proliferate.

Realists worship truth — for the ultimate lesson of history is that the truth of situations is often unpleasant. But Trump’s statements throughout the campaign have repeatedly revealed a basic disregard of facts.

Realists know that while the balance of power is not a panacea, maintaining an advantageous balance of power with rivals is generally in a nation’s interest. Russian President Vladimir Putin has upset the balance of power from Central Europe to the Middle East, something that we need urgently to rectify, at the very least for the sake of a stronger negotiating position with Russia. Trump appears to have no understanding of this. Indeed, rather than being realistic, his benign statements about Putin are dangerously naive.

Realists know that because values follow interests and not the other way around, a free-trading regime in Asia gives us a greater stake in the region so that we have more incentive to project our values there. A free-trading regime among our allies also counters China’s overbearing influence, which Trump claims he wants to curtail but — because he is not a realist — has no responsible idea about how to do it.

Realism is about moderation. It sees the value in the status quo while idealists only see the drawbacks in it. It is, therefore, wary of change. Trump, by contrast, wants an upheaval in the international system: from sparking trade wars, to increasing tensions with Mexico, to undermining NATO. Admitting the Baltic states into NATO may not have been altogether prudent from a realist point of view. But now that they are in the alliance, the credibility of NATO (and of the West) depends on defending them. Trump and his supporters clearly do not grasp this.

Realism, again, because it is a sensibility, and not a strategy, must be merged with a historically accurate vision of America’s place in the world. That place is no better defined than by the location of the Holocaust Memorial Museum adjacent to the Mall, showing that the Holocaust, which happened to Jews in Europe, has been by consensus granted entry into our national consciousness. This does not mean that the United States must intervene every time there is a major human rights violation somewhere — for that would be unrealistic. But it does mean that it must always take notice and, when practical, participate in a response, because America’s duty emerging out of the crucible of World War II and the Cold War has been to try — wherever possible — to expand the boundaries of civil society worldwide. Idealists are obsessed with this; realists are not. Realists know that national interest comes before any global interest. But realists, too, at least the respectable kind, harbor an internationalist vision.

History moves on. World War II and the Cold War recede. But the United States is the most well-endowed and advantageously located major state on Earth. That good fortune comes with responsibilities that extend beyond our own borders. Just look at the size of our 300-warship Navy and the location of our aircraft carriers on any given week. Realism is about utilizing such power to protect allies without precipitating conflict. It is not about abandoning them and precipitating conflict as a consequence. Hopefully, Trump will become a realist, but he has a long way to go.