Lehtikuva Lehtikuva / Reuters

We still do not know what hold Vladimir Putin has on Donald Trump, but the whole world has now witnessed the power of its grip.

Russia helped Donald Trump into the presidency, as Robert Mueller’s indictment vividly details. Putin, in his own voice, has confirmed that he wanted Trump elected. Standing alongside his benefactor, Trump denounced the special counsel investigating Russian intervention in the U.S. election—and even repudiated his own intelligence appointees.

This is an unprecedented situation, but not an uncontemplated one. At the 1787 convention in Philadelphia, the authors of the Constitution worried a great deal about foreign potentates corrupting the American presidency.

When Gouverneur Morris famously changed his mind in favor of an impeachment clause, he explained his new point of view by invoking a situation very similar to the one now facing the United States:

Our Executive was not like a Magistrate having a life interest, much less like one having an hereditary interest in his office. He may be bribed by a greater interest to betray his trust; and no one would say that we ought to expose ourselves to the danger of seeing the first Magistrate in foreign pay without being able to guard [against] it by displacing him.

The United States was then a comparatively poor and vulnerable country, so the Founders imagined corruption taking the form of some princely emolument that would enable an ex-president to emigrate and—in the words of Charles Cotesworth Pinckney—“live in greater splendor in another country than his own.” Yet they understood that even the most developed countries were not immune to the suborning of their leaders. As Morris said, "One would think the King of England well secured [against] bribery … Yet Charles II was bribed by Louis XIV.”

The reasons for Trump’s striking behavior—whether he was bribed or blackmailed or something else—remain to be ascertained. That he has publicly refused to defend his country’s independent electoral process—and did so jointly with the foreign dictator who perverted that process—is video-recorded fact.

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And it’s a fact that has to be seen in the larger context of his actions in office: denouncing the European Union as a “foe,” threatening to break up NATO, wrecking the U.S.-led world trading system, intervening in both U.K. and German politics in support of extremist and pro-Russian forces, and continually refusing to act to protect the integrity of U.S. voting systems—it all adds up to a political indictment, whether or not it quite qualifies as a criminal one.

America is a very legalistic society, in which public discussion often deteriorates into lawyers arguing about whether any statutes have been violated. But confronting the country in the wake of Helsinki is this question: Can it afford to wait to ascertain why Trump has subordinated himself to Putin after the president has so abjectly demonstrated that he has subordinated himself? Robert Mueller is leading a legal process. The United States faces a national-security emergency.