In the 1970s, an ideological struggle within the Republican Party pitted the views of Henry Kissinger, the secretary of state under Richard Nixon and Gerald Ford, against those of Ronald Reagan. Kissinger, a brilliant, German-born statesman, embraced realpolitik—a pragmatic, power-based approach to foreign policy that downplays morality and ethics. Reagan believed that although realpolitik might be pursued by other nations, the concept was alien to the United States. He thought that it undermined American ideals, which were a source of strength and not a weakness. He promised that if he became president, he would place human rights and the expansion of human liberty at the center of his national-security strategy.   In 1983, Reagan called the Soviet Union an “evil empire.” Time and again he framed the Cold War, and America, in explicitly moral terms. His loathing for totalitarianism was among the very few hatreds Reagan ever held, his biographer Edmund Morris said. During a May 1988 trip to the Soviet Union, he made a point of meeting with more than 100 dissidents. The New York Times reported at the time that senior Soviet officials complained that “a planned Presidential meeting with Soviet dissidents would be an unwelcome breach of superpower protocol.” Reagan’s determination to press the human-rights issue in Moscow “loomed as a potentially disruptive issue on the eve of his arrival,” the story said. “Moscow has traditionally resented what is seen here as an unwarranted and intrusive American assumption of moral superiority.” [Anne Applebaum: Trump has a new definition of human rights] No matter. For Reagan, America was a “shining city on a hill,” a moral example to the world. And even when America fell short, when its actions didn’t align with its ideals, when national interests overrode high-minded principles, its aspirations didn’t change. America’s ideals provided its people with a standard by which they could judge themselves. America’s Founders conceived of America in a certain way, too. It was a novus ordo seclorum, a “new order for the ages,” at the core of which lay a universalistic ethic. Abraham Lincoln, America’s greatest Republican and one of its two greatest presidents, saw the nation in profoundly moral terms; he described it as the world’s “last, best hope.” And almost every president has understood, in one way or another, that America cannot be pried apart from its ideals and remain America. The ethic in some nations may be that might makes right, but not in the United States. Until Donald Trump, that is. Now everything is different. Give Trump his due: He has never pretended to be something other than what he is in this area. His affinity for brutal dictators and authoritarian leaders—Kim Jong Un, Xi Jinping, Vladimir Putin, Recep Tayyip Erdoğan, Viktor Orbán, Mohammed bin Salman, Rodrigo Duterte—is well known. During the 2016 campaign, when MS NOW’s Joe Scarborough said Putin “kills journalists, political opponents, and invades countries,” Trump replied, “At least he’s a leader.” Besides, Trump added, “I think our country does plenty of killing also.” A year later, the Fox News host Bill O’Reilly pressed Trump on his repeated expressions of respect for Putin. When O’Reilly described Putin as a killer, Trump responded, “There are a lot of killers. You think our country’s so innocent?” It’s little wonder, then, that in his second term, a more liberated, less constrained Trump has repeatedly made it clear why he invaded Venezuela: He wanted its oil, and he was therefore entitled to seize it. But it hardly ends there. A few days ago, Trump said invading Colombia “sounds good to me.” He’s hinted at using force against Mexico. Last year, he reiterated threats to “take back” the Panama Canal. He’s talked openly about making Canada America’s “51st state.” And Trump and his administration are now openly declaring they will seize, by military force if necessary, Greenland, a self-governing territory within the Kingdom of Denmark, which was a founding NATO member. “We need Greenland from the standpoint of national security,” Trump recently said, describing the region as “covered with Russian and Chinese ships all over the place.” Since NATO was founded, in 1949, no member has attacked another. If that were to happen, it’s not clear that Article V, the collective-defense clause stating that an attack on one member is an attack on all and obligating other members to assist the attacked party, could successfully be invoked. But any such attack would surely destroy the greatest military alliance in history. [Read: Trump seizing Greenland could set off a chain reaction] On Tuesday, major European allies, including Denmark, said in a joint statement they would “not stop defending” the values of sovereignty and Greenland’s territorial integrity. “Greenland belongs to its people,” they said. “It is for Denmark and Greenland, and them only, to decide on matters concerning Denmark and Greenland.” Republican Representative Andy Ogles of Tennessee, in defending Trump’s stance on Greenland, referred to the United States as the “dominant predator” in the Western Hemisphere. He meant it as a compliment. Earlier this week, in an interview with CNN’s Jake Tapper, Stephen Miller, Trump’s most influential adviser, was asked, “Can you rule out that the U.S. is ever going to try to take Greenland by force?” Miller responded by saying that the official position of the Trump administration is that “Greenland should be part of the United States.” He wouldn’t take military force off the table. But what was most notable was Miller’s articulation of the MAGA worldview. “We live in a world in which you can talk all you want about international niceties and everything else, but we live in a world, in the real world, Jake, that is governed by strength, that is governed by force, that is governed by power,” Miller said. “These are the iron laws of the world since the beginning of time.” In Donald Trump’s America, the law of the jungle rules. The strong do what they can; the weak do what they must. A few days later, in an interview with the Times, Trump was asked if there were any limits on his global powers. “Yeah, there is one thing,” Trump said. “My own morality. My own mind. It’s the only thing that can stop me.” [Margaret MacMillan: This is the way a world order ends] That statement is worrisome on two levels. The first is that the man making it is the most powerful person in the world. He is also a malignant narcissist, consumed by hate and driven by vengeance. His mind is warped, his sense of morality corrupted. And yet his mind and his morality are the only checks on his power that he recognizes. Trump believes he is free to do whatever he wills. And it’s not at all clear who or what can stop him. The second reason Trump’s statement is worrisome is that he has changed the United States in fundamental ways. He has not only pried America apart from its ideals; he has inverted them. For a decade, he has been the overwhelmingly dominant figure in American life, and he has reshaped how hundreds of millions of Americans—including the great majority of Republicans and evangelical Christians—think about right and wrong, good and evil, justice and injustice. Many of the same people who once fiercely supported Reagan and opposed moral relativism and nihilism have come to embody the ethic of Thrasymachus, the cynical Sophist in Plato’s Republic who insists that justice has no intrinsic meaning. All that matters is the interests of the strongest party. “Injustice, if it is on a large enough scale, is stronger, freer, and more masterly than justice,” he argued. The United States under Trump is dark, aggressive, and lawless. It has become, in the words of Representative Ogles, a predator nation. This period of our history will eventually be judged, and the verdict will be unforgiving—because Thrasymachus was wrong. Justice matters more than injustice. And I have a strong intuition and a settled hope that the moral arc of the universe will eventually bend that way.