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What follows is the tale of how the campaign of a megalomaniacal Republican candidate colluded with a foreign power to swing an American presidential election. And how US national security agencies unearthed proof of the plot, but failed to intercede and stop it — leaving an incumbent Democratic president fuming in impotent fury.

As you doubtless suspected, we are speaking not about Donald Trump and his interactions with Russia, but another episode in modern presidential history — namely, Richard Nixon’s off-the-books diplomacy with South Vietnam, in advance of the 1968 elections. In that year, Nixon employed secret emissaries to urge South Vietnamese officials to stall, and thus wreck, President Lyndon Johnson’s election eve effort to convene a peace conference and bring an end to the Vietnam War.

Johnson learned of the Republican intrigue but, like President Barack Obama and US security agencies almost 50 years later, declined to go public without proof of the candidate’s direct, personal involvement.

Although the Trump-Russia story has yet to fully unfold, some of the parallels are striking. The earlier episode, moreover, offers cautionary lessons for the left.

The story of “the Chennault Affair,” as the episode was known, and its impact on the 1968 election, should throw some cold water on the notion that this month’s stunning revelations — that Donald Trump Jr. and two other Trump confidants met with a reputed emissary of the Russian government with the purpose of conspiring against Hillary Clinton — will lead to President Trump’s swift downfall.

Nixon won election in 1968, and reelection in a 1972 landslide. “They got away with it,” Johnson’s national security adviser, Walt Rostow, would write, in a bitter memo to his files, in 1973.

Gleeful liberals would be fools to treat lightly the hard work facing them in the 2017 and 2018 off-year elections, and the 2020 presidential race. They underestimated Trump last fall, and look what that got them.

There are other lessons. While some observers have treated the Donald Trump Jr. emails as the proverbial smoking gun, it’s also the case that we don’t know the extent to which then-candidate Trump was aware of that meeting — or aware of other contacts with Russians. Special counsel Robert Mueller's investigation, or the intrepid efforts of journalists, may yet turn up such information, but the Nixon episode suggests that governments may yield secrets, and history its lessons, begrudgingly.

Indeed, confirmation of Nixon’s personal direction of the Chennault Affair did not come until this year when (horn-blowing moment at hand) I published the evidence in my new biography, Richard Nixon: The Life.

Anna Chennault served as a contact point between Nixon’s campaign and the South Vietnamese government

The Chennault Affair takes its name from Anna Chennault, Nixon’s chief conduit to the South Vietnamese. She was a China-born doyenne and Republican fundraiser, and a member of good standing in the militant, conservative China Lobby an anti-communist group advancing the interests of the nationalist Chinese government in Taiwan. Some called her the Little Flower; others, the Dragon Lady.

Like Trump and his aides in their dalliance with the Russians, the Nixon campaign and the South Vietnamese each saw the advantage of an election-year relationship.

According to Chennault’s memoirs, and those of Bui Diem, who was then the South Vietnamese ambassador to the United States, the two of them met with Nixon and his campaign manager, John Mitchell, in early and/or mid-1968. By Chennault's account, one meeting took place at Nixon’s Fifth Avenue apartment (just up the street from where Trump Tower now sits, and where, in June 2016, Trump Jr., campaign chieftain Paul Manafort, and the president’s son-in-law, Jared Kushner, took a meeting with Russian lawyer Natalia Veselnitskaya, and several others).

Diem was informed by Nixon and Mitchell that Chennault would serve as their campaign’s intermediary.

We don’t know precisely what Trump’s aides thought to get from the Russians, and exactly what (besides the old naval sentiment of “Confusion to our enemies!”) Vladimir Putin’s government hoped to gain when helping Trump. But today we have a clear understanding of Nixon’s motivations.

Nixon was worried as Election Day drew near. He had entered the home stretch with a formidable lead over Humphrey. One of Nixon’s staffers, a young number cruncher named Alan Greenspan, had brashly predicted that Republicans would win 461 electoral votes, with Humphrey taking only 11. But Nixon’s lead in the polls began to shrink as working-class voters returned to their ancestral home in the Democratic Party.

Nixon recalled the 1966 congressional campaign, when Johnson had flown to Manila on the eve of the election for a conference with Asian leaders and announced a new Vietnam peace plan to sway the voters. The Republican candidate feared Johnson was working on another October surprise.

Nixon worried that Johnson would use foreign policy to affect the election

He bitterly remembered, as well, the 1960 election that he lost to John F. Kennedy, on an election eve that author Theodore White christened “the night of the gnomes.” It was a night, White wrote, when “political thieves … were counterfeiting results all across the nation.” In Illinois and Texas, White concluded, Democratic “vote-stealing had definitely taken place on a massive scale.”

“We won, but they stole it from us,” Nixon told a colleague. It is impossible to prove what happened that night, but Nixon believed the Kennedys had employed the rankest sort of political larceny to win. The experience left him with a fierce resolve to never be out-cheated again.

It was Henry Kissinger, an adviser to the Johnson administration and a less-than-discreet observer of American diplomatic maneuverings, who alerted the Nixon campaign in late September, and again in early October 1968, that trouble might be brewing. There was “a better than even” chance, Kissinger told Mitchell, that Johnson would call a pause to the aerial bombardment of North Vietnam.

“RN th[i]nks attempt by LBJ to get pause before election,” Nixon’s campaign chief of staff, H.R. Haldeman, recorded in his notes. “Is attempt to build up idea war is at end.”

In fact, Johnson and his team had good reason to believe that a bombing pause would yield results. The Russians have never been opposed to meddling in American elections (though not on a scale like the 2015-2016 intrusions), and the Soviet leaders did not much like the red-baiting, anti-communist Nixon. To help Humphrey become president, they pressed their clients in North Vietnam to agree to a ceasefire and hold talks to end the war.

“My colleagues and I think — and we have grounds to do so — that complete cessation by the United States of bombing and other acts of war … could contribute to a breakthrough,” the Soviet premier, Alexei Kosygin, wrote Johnson.

“This is treason,” Johnson told his old friend Everett Dirksen, the Senate Republican leader

Johnson’s aides performed their due diligence, and reached the conclusion that the offer was genuine. “All of us know that, with all its uncertainties, we have the best deal we now can get — vastly better than any we thought we could get since 1961,” the national security adviser, Rostow, wrote the president. “If we go ahead we know it may be tough. But with military and political determination we believe we can make it stick. … None of us would know how to justify delay.”

Johnson saw a glimmer of peace. Nixon believed it was a ruse. In such misunderstandings the tragic lurks. In the years to come, millions more Asians, and 20,000 more American soldiers, would die in Indochina.

Johnson smells a rat

On October 31, Johnson announced his bombing halt, and Humphrey’s campaign soared toward the November 5 finish line. But South Vietnamese President Nguyen Van Thieu dragged his feet, announcing his reluctance to join in peace talks. LBJ already had a “credibility gap” when it came to Vietnam; he had offered rosy outlooks and promises before. Without Thieu's support, the bombing halt looked like a cheap political trick, employed to get Humphrey elected.

South Vietnam’s motivation was clear to the president. “We could stop the killing out there,” LBJ told Senate Republican leader Everett Dirksen of Illinois, in remarks captured on the Johnson White House taping system. “But they’ve got this … new formula put in there — namely, wait on Nixon. And they’re killing four or five hundred a day waiting on Nixon.”

The seething Texan erupted when Rostow (who had picked up rumors on Wall Street) reported that the Nixon campaign, and specifically Chennault, was behind Saigon’s reluctance. Johnson put his security agencies to work, and soon the FBI, CIA, and NSA were focusing their surveillance tools on the South Vietnamese, Chennault, and her associates.

The eavesdropping yielded fruit. “Anna Chennault contacted Vietnam Ambassador Bui Diem,” one report noted, “and advised him that she had received a message from her boss … which her boss wanted her to give personally to the ambassador. She said the message was that, ‘Hold on. We are gonna win. … Please tell your boss to hold on.’”

Johnson got Dirksen on the phone again. “I’m reading their hand, Everett,” he told his old friend. “This is treason.”

After hearing from Dirksen, Nixon called Johnson. The Republican candidate denied it all. “My God, I would never do anything to encourage … Saigon not to come to the table,” he assured LBJ.

Rostow urged the president to “blow the whistle” on the Republicans and “destroy” Nixon’s candidacy. Johnson — and Humphrey, who by now had been informed of the plot — faced difficult questions, quite similar to those confronted by Barack Obama last year.

Without proof of the Republican candidate’s direct and personal involvement, could a Democratic White House accuse him of conspiring with a foreign power to swing the election? What if Nixon were elected anyway? It would be "inimical to our country's interests," Defense Secretary Clark Clifford warned Johnson, if a President Nixon were left to govern in a crippled condition. Johnson and his aides balked, moreover, at disclosing his authorization of government surveillance on a political foe — which might have caused an uproar on its own. Might it not appear, in the heat of a presidential campaign, like a Democratic dirty trick?

Even Rostow admitted that they had “no hard evidence that Mr. Nixon himself is involved.” And so Johnson, like Obama, kept the information from the American electorate. On November 5, in one of the closest presidential elections ever, Nixon won with 43.4 percent of the vote in a three-way contest with Humphrey, who received 42.7 percent of the votes, and a third-party candidate, the Alabama segregationist George Wallace (13.5 percent.)

Nixon's actions were not "treason" — South Vietnam was an ally, not an enemy. But they fit actions proscribed by the Logan Act, a little-used statute adopted by the Founding Fathers that was enacted to prohibit this very sort of meddling by private citizens in the diplomacy of the United States. Even Kissinger, who claimed not to have known of Chennault's behind-the-scenes efforts, would concede in his memoir Ending the Vietnam War that, at the very least, Nixon's actions were "highly inappropriate if true."

The decades-long effort to conceal Nixon’s overtures to South Vietnam

Hazy, unconfirmed reports of the Chennault Affair appeared in the newspapers almost immediately, and in books about the 1968 campaign by White and others, but Johnson and Rostow had the relevant Johnson administration documents locked up for decades, in a folder known as "the X envelope." It was not until recently that the release of the records and White House tapes by the Lyndon B. Johnson Presidential Library put flesh on our then-skeletal knowledge of the affair. (For the fullest account of Nixon's intrigue, and how it has come to light over the years, see Chasing Shadows, a 2014 book by Ken Hughes, a researcher at the University of Virginia's Miller Center.)

Nixon lied to Johnson, and he lied again when grilled by David Frost about the episode in their famous 1977 televised interviews, and elsewhere through the years. The former president’s lawyers fought for decades to maintain control of his most sensitive political files, which were not released to the public until well into this century.

In those files are Haldeman’s notes from the 1968 campaign, recording the Nixon campaign’s discussion of how to “monkey wrench” Johnson’s election eve maneuvers. Haldeman recorded Nixon’s instructions to “Keep Anna Chennault working on SVN” and to have other emissaries press Saigon to resist.

Luke Nichter, one of the country’s leading experts on the Nixon tapes, and a scholar of his presidency, warns that our propensity to view Tricky Dick as villainous may lead us to harsher judgments of his actions than the evidence warrants. Duly noted. Here, and in my book, I have tried to present Nixon’s motivations in the best possible light — that of someone cheated, and singed, by Kennedy and Johnson.

Nichter rightly notes, as well, that for historians an important question lingers: Just what impact did the Chennault Affair have? And, indeed, the droves of variables forestall a conclusion that Nixon's meddling, alone, cost the United States an opportunity to end the war in the fall of 1968. The stubbornness displayed by both North and South Vietnam in future negotiations, and history's analysis of the internal political machinations in Saigon and Hanoi, preclude so ready a judgment.

In a long, reasoned examination of the incident in A Tangled Web, his book on Nixon’s foreign policy, the Democratic national security expert William Bundy did some Monday morning quarterbacking and concluded that Johnson’s hopes for a 1968 settlement, while genuine, now seem extravagant. “Probably no great chance was lost,” he wrote. That’s also the verdict I reached in my Nixon biography.

But Bundy closed his discussion of the affair with an ominous note about the leverage Nixon’s actions gave Thieu, the South Vietnamese president. In this there is a parallel to the Trump campaign’s interactions with the Russians, and what Vladimir Putin may have hoped to gain.

Thieu emerged from the Chennault Affair armed with knowledge of the Nixon campaign’s secret machinations, and a belief that “Nixon owed him a great political debt,” Bundy wrote. “The effect of such a debt on future dealings between the two men … was in my judgment the most important legacy of the whole episode.”

Time and again, in their difficult relationship, an emboldened Thieu would dig in his heels, hindering Nixon’s efforts to bring the war to a quick conclusion.

“That a new American President started with a heavy and recognized debt to the leader he had above all to influence was surely a great handicap,” Bundy wrote.

It’s a relevant consideration today, as federal investigators ponder whether Russia has the evidence with which to blackmail or extort Trump administration officials — and so influence American foreign policy.

John A. Farrell is the author of Richard Nixon: The Life, which was published in March.

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