How does the House of Representatives’ impeachment inquiry of President Donald Trump compare to the one that forced Richard Nixon to resign 45 years ago? To answer that question, it’s important to look at what matters to the impeachment process and what doesn’t.

Nixon resigned as president in August 1974. Tapes of him discussing the break-ins at Democratic Party headquarters at the Watergate building in Washington, D.C. were released on Aug. 5, and he resigned four days later. Until that point, a substantial segment of the U.S. electorate continued to support him. Nixon had won a landslide reelection in 1972 by defeating George McGovern, who ran on an anti-Vietnam War platform. That platform was perceived by many as supporting what was then called the “counterculture,” which was seen as a systematic attack by a marginal group on American middle-class values. Nixon positioned himself as the spokesman for this “silent majority,” which was seen as the politically subdued core of American society and values.

Nixon did not simply run against McGovern or the counterculture. He also ran against the media, which he saw as having been hostile to him well before his first election, hostile to the war in Vietnam from the beginning, and unwilling to praise him for his foreign policy initiatives (including the opening to China and detente with the Soviets) and his championing of middle-American values. Looking back at Nixon’s press conferences, the hostility and contempt of the reporters was palpable, as was Nixon’s defensive anger.

The Watergate scandal began in August 1972 and developed with increasing intensity for two years. There was much discussion of impeachment or criminal indictment of the president, but this was impossible. Many of Nixon’s supporters viewed the unfolding scandal as something manufactured by the president’s political enemies and the media. Interestingly, despite Nixon’s landslide victory, both houses of Congress were controlled by the Democrats, who held hearings on the Watergate affair in the summer of 1974.

The Democrats understood that while they might be able to impeach the president in the House of Representatives, they did not have anywhere close to the two-thirds majority needed to convict in the Senate. Given the passions on both sides, the Democrats were loath to bring an impeachment vote up in the House knowing that conviction was impossible. It would be seen as useless political melodrama. In addition, they could not try him on the same offense later. Likewise, senators did not want the House to put them in a position of holding a vote that might fail. Since both houses were controlled by the same party, they were equally solicitous of each other.

The problem for the Democrats at that time was the deep division in the country. According to polls, a majority of voters were hostile to Nixon, but he retained enough support — in the 40% range — to deter Democrats running in districts that were close (and many were close in 1974). Since impeachment is a political rather than a judicial process, a powerful minority of voters saw it as a desire to reverse McGovern’s defeat. Indeed, the number of voters who opposed Nixon politically was larger than the number of voters who wanted him impeached. The political risk of alienating those voters was too great.

The ‘smoking gun’

The debate might have gone on indefinitely but for the emergence of a “smoking gun” — evidence so conclusive that even Nixon’s Republican supporters could not ascribe it to Democratic or media manipulation. The smoking gun was the revelation that Nixon had taped many of his office conversations and that some included conversations on Watergate. The House and Senate demanded the tapes, but Nixon refused to release them. That alone started to erode his political support on the theory that he would only hide the tapes if they were harmful to him.

“ A group of senior senators told Nixon that he would be convicted by the Senate if it came to a vote and convinced him to resign. ”

After the courts ordered the release of the tapes, it was discovered that one of them had been erased while others clearly implied Nixon either had knowledge of the cover-up or ordered the break-in himself. The mood among his Republican supporters and in the Senate then shifted. A group of senior senators told Nixon that he would be convicted by the Senate if it came to a vote and convinced him to resign.

The key to this event had little to do with members of Congress. It had everything to do with Republican voters, who were persuaded that, while the attacks on Nixon had been carried out for political reasons, he was guilty and had to be removed. The smoking gun had brought them there (and Republican anger at the media and the Democrats was no less then than it is today). So despite the loathing for Nixon’s enemies, there was a sea change among his supporters, such as never took place during the impeachment of President Bill Clinton. During the Clinton impeachment, Democratic voters did not agree that there had been a smoking gun requiring conviction, and the Senate found Clinton not guilty.

Neither the House nor the Senate held the power to remove Nixon from office. Nor did those who despised him. That power was held by Nixon’s supporters, who represented a substantial minority by 1974 that could sway state and local elections. Their standard for removal was far higher than others’, and without a smoking gun, the scandal would likely have lurched on indefinitely. But there was a smoking gun, one that tore away illusions about Nixon. Yet Nixon’s supporters never forgave the Democrats for trying to destroy him before they had a smoking gun, and for 12 years after Jimmy Carter, Republicans dominated the presidency.

“ The United States today is at a point similar to where it stood in 1974. ”

The United States today is at a point similar to where it stood in 1974. The country is divided into two camps, as alienated from each other as were middle America and the counterculture. The Democrats are becoming the political party of the current culture, and the Republicans are the party seeking to hold on to past values. Trump has the support of a minority of voters, which still represents a significant segment of the electorate. He and his backers hold the media responsible for the political crisis, and the media is strongly arrayed against Trump. The passion on both sides is extreme. The president’s opponents and supporters not only are extraordinarily convinced of their positions but, more important, have little contact with each other. Both groups represent hostile tribes, much as it was during the Nixon crisis.

But the important thing to keep in mind is that opposition to impeachment so far is larger than Trump’s own support base. This is the single most important fact that will determine the future course of this debate. Just as the Republicans in 1974 required a smoking gun to support impeachment, so too does the system today.

“ The public, not politicians, will decide what really is a smoking gun. ”

The question is whether Trump’s Ukraine affair is that smoking gun. There have been many allegations leveled against Trump that were supposed to be smoking guns — but turned out not to be. Ultimately, the public, not politicians, will decide what really is a smoking gun. And if one were found, the public mood would shift in support of impeachment. It would slash support for Trump into the 20s or less. That would change the decision-making process of politicians in both parties.

What happened with Nixon had many predecessors, but it wasn’t until the tapes were released that his presidency collapsed. There are many precursors with Trump as well, but none were sufficiently convincing to cause the voters to shift dramatically. As in 1974, it is not the Democratic voters that are decisive but the Republican ones. It was their shift that freed Republican senators to change their position and guarantee Nixon’s removal from office. Today, the Democrats have fixed positions, and they can’t remove Trump from office. Only the Republicans can, and their voters aren’t convinced.

There are two things that the Nixon and Trump impeachment processes have in common. The first is that the social divide during both events was profound. The second is that for a couple of years before Nixon’s end, and before this moment for Trump, there were endless assertions of impeachable offenses that alienated the Nixon faction and energized his enemies. That process raised the bar for conviction, because it made the smoking gun essential. So many accusations arose, all of which ultimately went nowhere, that incontrovertible evidence — the tapes — became necessary.

On the current claim against Trump — that he tried to persuade the Ukrainian government to investigate former Vice-President and 2020 presidential candidate Joe Biden — my opinion or yours really doesn’t matter. The key is whether this charge breaks the back of Trump’s support, leaving him with only a handful of supporters. In the Nixon era, evidence exhaustion was overcome by the tapes. The issue now is whether anything will come out that can overcome evidence exhaustion in this case.

If Trump’s political support remains as is, he will not be convicted. Most understand that impeachment and conviction are a political, not judicial, process, but many fail to see that this doesn’t mean politicians get to decide what happens. Politicians want to be reelected, so in the end, as is appropriate in a republic, the people will decide this issue. They will decide if Ukraine is a smoking gun.

George Friedman is the founder and chairman of Geopolitical Futures LLC , an online publication that explains and forecasts the course of global events. Republished with permission.

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