David Greenberg, a professor of history and journalism and media studies at Rutgers, is a contributing editor at Politico Magazine. He is the author of several works of political history including, most recently, Republic of Spin: An Inside History of the American Presidency.

Impeachment is back on the table. Leading up to the fall midterms, Democrats studiously shunned talk of removing President Donald Trump from office, knowing that while it might inspire their fervent partisans, it would also do the same for his. But lately the case for impeachment has been made soberly by New York Times columnist David Leonhardt and more pithily by newly elected congresswoman Rashida Tlaib. Impeachment enthusiast Tom Steyer just decided not to run for president but to push his pet cause instead.

Talk of impeaching Trump has become so common, in fact, that it’s easy to forget just how exotic a constitutional mechanism it has traditionally been. Congress has undertaken impeachment proceedings against only three presidents—Richard Nixon, who resigned; and Andrew Johnson and Bill Clinton, who were acquitted. Those facts alone should sound a note of caution. And while it’s always risky to form judgments based on just three episodes—one of them 150 years ago—the stories of those three proceedings also suggest the hazards of an impeachment drive without broad-based support. Today, with Democrats in charge of the House of Representatives, this history deserves attention.




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Johnson is considered one of the worst presidents ever. He took office after Abraham Lincoln’s assassination in 1865. After the Civil War, as Americans debated the terms for readmitting the secessionist states, Johnson was lenient toward the South and hostile toward former slaves. Perpetually battling the Republicans in Congress over Reconstruction policy, he vetoed a string of important bills, only to be overridden by supermajorities.

Johnson made matters worse when he traveled the country to support conservative candidates in the 1866 midterm congressional campaign. On that tour, the president—who in his willfulness, grandiosity, vulgarity and disregard for the dignity of his office prefigured Trump more than any other White House occupant—bellowed at hecklers, branded his Republican nemeses traitors and likened himself to Jesus Christ. But his belligerence backfired, bolstering Republican margins in both houses come November.

In the new year, the Republicans passed the Tenure of Office Act—a constitutionally dubious statute that forbade the president from removing a Cabinet officer until the Senate approved a successor. The aim was to stop Johnson from replacing Lincoln holdovers with lackeys who would undermine their Reconstruction plans. Flouting the new law, Johnson defiantly sacked his Secretary of War, Edwin Stanton—and named a new one, all without Senate approval.

While Stanton barricaded himself in his office for two months, refusing to step down, a congressional committee quickly returned 11 articles of impeachment, which the full House approved in just two days. Two articles dealt with Johnson’s behavior during the midterms, which congressmen said brought their body into disgrace and contempt—a nakedly political standard that could be wielded against any president who crossed Congress. Most of the articles, however, centered on the Tenure of Office Act.

In the Senate trial, Johnson’s fate lay with a dozen moderate Republicans. Though not fans of the president, they knew his successor would be Senate President Pro Tempore Benjamin Wade, a “Radical Republican”—not an outcome they relished. So when Johnson, who was in his last year anyway, signaled that he would stop obstructing their Reconstruction plans, he secured several moderates’ support and escaped conviction by a single vote. Stanton agreed to resign.

Few people today doubt that the Republicans were right about Reconstruction. But it’s also widely agreed that in impeaching Johnson over political differences, they overreached. As Republican Senator Lyman Trumbull of Illinois said in urging acquittal, conviction would have meant that “no future president will be safe who happens to differ with a majority of the House and two-thirds of the Senate on any measure deemed by them important. Blinded by partisan zeal, they will not scruple to remove out of the way any obstacle to the accomplishment of their purposes. And what then becomes of the checks and balances of the Constitution?”

Johnson’s trial settled what had been an open question: The constitutional mechanism of impeachment was categorically different from a parliamentary vote of no confidence. Johnson’s acquittal, however narrow, confirmed that a president must not be removed for mere policy differences—thus setting a high standard. Consequently, for the next century impeachment would be scarcely considered at all.

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The power of the presidency as an institution grew in the 20th century, further diminishing Congress’ willingness to impeach presidents. Only after the 1960s, when established authority of all forms came under assault, did the prospect of ejecting a sitting president again seem viable. Nixon—a president perhaps more heedless even than Trump of constitutional strictures and political niceties—provided ample cause.

Despised and distrusted since his days as a congressman, Nixon encountered fierce opposition from his inauguration onward—an opposition no less ferocious than today’s anti-Trump “resistance.” The activists who had pressured President Lyndon B. Johnson to step aside in 1968 made clear their desire to dispatch Nixon, too. As early as November 1969, during nationwide anti-Vietnam War rallies, activist Sidney Lens urged Nixon’s impeachment; after the president’s invasion of Cambodia in 1970, others did so too. In 1971, Representatives Bella Abzug and Pete McCloskey pushed an impeachment resolution centered on Nixon’s warmaking.

Yet even though Nixon had already secretly suborned illegal activities—starting with the 1969 wiretapping of journalists and government officials—the first-term shouts for impeachment struck most Americans as overreaction or posturing. Certainly they were premature. In May 1972, when a group called the National Committee for Impeachment placed a two-page in the New York Times, the paper’s press operators initially refused to run their machines because they considered the ad’s claims to be traitorous.

That same month, ironically, Nixon’s henchmen were burgling the Democratic Party headquarters at the Watergate building; when they returned to fix a bad wiretap, they were caught. For months afterward, disclosures about the White House’s role failed to disrupt Nixon’s march to reelection. In 1973, however, news from both the burglars’ trial and the newly convened Senate Watergate Committee—whose jaw-dropping hearings were televised to rapt audiences—began to reveal the extent of the president’s lawlessness. Public opinion started to move.

Not until October, though, was impeachment talk widely treated as legitimate. The trigger was the Saturday Night Massacre, the resignation of the top two Justice Department officials after Nixon ordered them to fire the Watergate prosecutor. And it wasn’t until February 1974, moreover, that the House Judiciary Committee took up impeachment. At that point, bipartisan support for Nixon’s ouster had grown considerably. By the summer, when the committee voted on the question, several Republicans crossed the aisle to vote aye—giving the committee’s verdict a moral authority that the campaign against Johnson never possessed. It was congressional Republicans, too, who told Nixon he couldn’t survive a Senate trial, persuading him to resign.

It was equally significant that the House committee rejected impeachment articles relating to the Vietnam War and Nixon’s tax cheating. The former, it was understood, lay within a president’s purview as commander in chief; the latter, though a crime, was too petty to warrant impeachment. Congress was in effect building on the Johnson-era criteria for presidential impeachment, affirming that constitutional issues had to be at stake. The articles of impeachment that passed centered on Nixon’s obstruction of justice (such as using the CIA to try to thwart the Watergate investigation and paying hush money to the Watergate burglars), abuse of power (such as using the IRS and FBI for political vendettas) and defiance of congressional subpoenas.

If the overreach of Johnson’s enemies discredited impeachment for a long time, the deliberative process regarding Nixon was taken as proof that “the system works”—that even the so-called imperial presidency wasn’t beyond restraint. Ironically, though, the effective use of impeachment as a tool in 1974 meant it was no longer unthinkable for Republicans, nursing their wounds, to consider doing the same. They tested that proposition in 1998—although, in a further irony, it was Nixon’s example that in the end led Americans to put Clinton’s offenses in perspective.



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After he resigned, Nixon was confined to the national doghouse. Most Americans viewed his transgressions categorically different from other presidents’. But for some die-hard Republicans, Watergate was an unhealed wound. Loyalists tried to relativize his crimes; his former speechwriter William Safire, now a New York Times columnist, attached the suffix “–gate” even to minor scandals as if to render Watergate one of many. That maneuver long ago became a cultural tic, used by almost everyone and untethered from the motive of minimizing Nixon’s crimes.

In 1992, having held the White House for 12 years—the longest stretch by any party since Harry S. Truman left office—many Republicans resented the very fact of Clinton’s election. Throughout his presidency, Clinton was harried by Republican investigations. But by 1998, Republicans had little to show for these efforts. Clinton's affair with White House intern Monica Lewinsky, disclosed early that year, gave them a cudgel.

In January of that year, independent counsel Ken Starr—charged with investigating a land deal—claimed that Clinton not only had had an affair but had acted illegally to hide it. Suddenly, impeachment talk exploded—endorsed as an imminent possibility by no less than George Stephanopoulos of ABC News, whose prior role as Clinton’s White House aide lent credibility to the scenario. In March, the House Republicans set the impeachment machinery in motion. But Starr flailed about for months trying to get Lewinsky to testify. And as the foofaraw continued, the public adjusted its expectations, acknowledged Clinton’s foibles and urged Washington to move on.

To most of the public, the partisan nature of the impeachment drive was obvious. Among Senate Democrats, only Joe Lieberman of Connecticut even flirted with impeachment and he eventually declined to support it. Five House Democrats ultimately did so, while 81 Republicans voted against at least one count. Meanwhile, Starr’s overt religiosity and Republicans’ hypocrisy about sexual misbehavior—House Speaker Newt Gingrich, for one, was having an affair with a staffer the whole time—denied the impeachment push the broad-based legitimacy of the investigations into Nixon.

Throughout the Lewinsky crisis, Watergate loomed as a negative example, setting a standard of wrongdoing that Clinton’s offenses conspicuously failed to meet. When Starr decided to explicitly join the Republicans’ demand for Clinton’s removal, his ethics adviser Sam Dash—a former Senate Watergate Committee counsel, whose presence on Starr’s team had lent it a patina of respectability—resigned in protest.

Even after Clinton admitted the affair and apologized, Republicans misread the public mood and forged ahead with impeachment proceedings—resulting in a historically rare loss of congressional seats in the November midterm elections for the party not controlling the White House. They held onto enough seats to impeach him on two counts—perjury and obstruction of justice—in December, but as they did so, his popularity soared to 73 percent. Surprising no one, Clinton was acquitted in the Senate with considerable bipartisan support.



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Most Americans since then have continued to view the impeachment drive as partisan and unwarranted, even if they look askance at Clinton’s behavior. His defenders’ arguments—that even lying about his affair wasn’t a constitutional offense—were never seriously challenged. His acquittal in effect reaffirmed that impeachment shouldn’t be used for light and transient causes. Under both George W. Bush and Barack Obama, partisans at times issued demands for impeachment but party leaders always rejected them. Without evidence of wrongdoing so alarming that it would cause some of the president’s own supporters to break ranks, any such effort would lack the legitimacy it needs.

Needless to say, Congress shouldn’t shrink from investigating specific areas of Trump’s conduct, including those Leonhardt enumerated last week. Now that they’re run by Democrats, House committees can probe the legality of Trump's mingling of government and private business. They can study the constitutionality of his firing FBI Director James Comey—and of other possible obstructions of the collusion inquiry. And they can probe whether he has systematically placed Russia’s interest before America’s. Public hearings could be as revealing as those the Senate Watergate Committee held in 1973.

But Democrats would also be wise to trust House Judiciary Chairman Jerrold Nadler, who wants to defer talk of impeachment until such investigations progress. Without support from “a good fraction of the opposition” party, Nadler said, an impeachment drive would “tear the country apart.” And there is another reason to hold off on impeachment as well: Given the constitutional requirement for a supermajority of Senators to convict, any effort to remove Trump from the White House today would—inevitably and catastrophically—fail. Barring a highly improbable flip-flop by some 20 Senate Republicans, impeachment is simply not going to happen. Rather than indulge the hopes of their most fervently anti-Trump constituents, Democrats might be wiser to press on with investigations while leveling with voters that the best shot at ending Trump’s presidency anytime soon will come at the ballot box in 2020.