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In the spring and again the summer of 2016, a large chunk of the Republican foreign-policy and national-security establishment publicly denounced then-candidate Donald Trump as unfit to serve as president. In the months and years that followed, those of us who took that stand have attracted a fair amount of reproach: We were a gang of unrepentant neocons; we were simply wrong about how much danger he posed; some, although not all, of us were morally suspect for having been in favor of the Iraq War.

However, we were right. And we were right because at the heart of our critique was a view of Donald Trump’s character, not his policy preferences. “He is fundamentally dishonest,” we wrote in March. “Mr. Trump lacks the character, values and experience to be president,” we wrote in August. Those who signed those letters have been accused of prissiness, a fastidiousness about the rough game of politics that calls into question our understanding of the world.

And indeed, this focus on character more than policy may baffle some who have heard the remark, attributed to the 17th-century English diplomatist Henry Wotton, “An ambassador is an honest gentleman sent to lie abroad for the good of his country.” Surely students of international affairs, whose preoccupation is the study of a world in which law is often weak and common norms of behavior absent, should not worry too much about dishonesty, lechery, and cheating.

Actually, they do—and recent events show why they are right to do so. The Ukraine quid pro quo crisis, in which it becomes increasingly clear that the president attempted to withhold desperately needed military aid from Kiev in order to extract political hit jobs on his opponents, shows why character matters. In the world as it is, it’s very simple for foreign policy to ease the path to the corruption of domestic politics. Indeed, that was one of the great fears of the Founders of the United States, and with reason. In 1797, Talleyrand, that consummate cynic, indirectly demanded a £50,000 bribe to ease Franco-American relations. Half a dozen years later, the vice president of the United States, Aaron Burr, put out feelers to the British about splitting off part of the United States in return for half a million dollars.

The self-inflicted wound of the administration’s Syria policy—its wrenching and unnecessary abandonment of Kurdish allies who spilled their blood waging war on our behalf—is another example of bad character leading to disaster. Much of any country’s power in international affairs comes from its reliability and predictability: The “madman” thesis supposedly espoused by President Richard Nixon has its limits. Because international affairs is not ruled by contract and law the way domestic politics often is, one’s consistency matters. It is like the diamond business, famously conducted less by documents than by a handshake. Reputation matters, and those who think otherwise are themselves naive.

By abandoning the Kurds on a caprice, the United States has ceded predominant influence in the Middle East to Russia and Iran; it has paved the way for the resurgence of the Islamic State; it has impaired its ability to shape Iraqi politics; and it has put its principal ally in the region, Israel, in a worse situation. Above all, it has shown that its word is meaningless.

Good diplomats do not lie. Rather, they are trained to be exquisitely precise, both in their record-keeping and in their articulation of their own country’s views. They may be too nuanced at times, too keen to find the formula that is just ambiguous enough to satisfy (or lull) all parties. But, by and large, they are allergic to lying, partly because of their own values, and partly because they know how dangerous it can be.

And they are patriots. The diplomats of the Department of State are a disciplined, hierarchical body; they will, when necessary, don flak jackets and helmets in dangerous places, but for the most part they simply want to go out and represent their country. And unless you have worked there, you may not realize how committed they are to what the United States stands for, to its values and its founding principles. In this, they resemble the leadership of the United States military, which, to a remarkable degree, shares this values-driven, or at least values-informed, approach to foreign policy.

In recent weeks, we have seen diplomats—the former ambassador and acting ambassador to Ukraine, most notably—take the uncomfortable road of telling truths that are mortifying to the administration. It is not surprising. They know what happens abroad when the most powerful country in the world, the one that has done most to create international norms that keep the peace, behaves duplicitously, dishonestly, and purely out of a shortsighted conception of self-interest. They know, too, that the American alliance system is the country’s greatest international asset, and that the system rests above all on American reliability, predictability, and honesty.

The Russians and the Chinese understand this as well. It is no coincidence that the rhetorical attacks of the Russian government on the United States and its campaign of covert political warfare play to the most cynical themes of a disillusioned age. Russia’s internet operatives, like its snarling representatives in the physical world, favor “whataboutism.” They have as their most successful target the president of the United States, who prefers the company of dictators—who shut down the press, who bribe and steal and repress—to that of democratic leaders, who have some lines they cannot or will not cross.

The president presents his cynicism, and that of his acting chief of staff and his erratic personal lawyer, as tough-guy street smarts. It’s not. Their cynicism is the product of a peculiar and not particularly savory business microclimate in New York, and his own disordered personality. It has yielded nothing in foreign affairs beyond embarrassingly failed negotiations with North Korea, a trade war with China, betrayal of allies in the Middle East, and a cold war with Iran in which the United States looks to be unable to protect Saudi Arabia. It will get worse as the president becomes more erratic and more incapable of attracting competent subordinates.

Sir Henry Wotton was a poet as well as an emissary of King James I. He described in “The Character of a Happy Life” the satisfaction of one

Who hath his life from rumours freed;
Whose conscience is his strong retreat;
Whose state can neither flatterers feed,
Nor ruins make accusers great;

The drama unfolding before us is of a president who is, in foreign affairs at least, powerful and boastful, but whose life, measured by the standard of that wise diplomat, is thoroughly unhappy. How this ends has always been clear to those who cared to see.

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