There have been four presidential-impeachment processes since 1787. None has resulted in removal, but all four had seismic political consequences.
Andrew Johnson was not removed in 1868, but he was not renominated, either, and failed to gain the second term he so wanted.
Richard Nixon was not removed in 1974; he resigned amid an immense scandal.
Bill Clinton was not removed in 1998. Instead, Clinton’s became the first administration since Reconstruction to gain congressional seats in the sixth year of its term. His chief opponent, House Speaker Newt Gingrich, resigned instead, as did Gingrich’s presumptive successor, Bob Livingston, who confessed to an extramarital affair of his own.*
Donald Trump was not removed in 2020, but he lost the presidency, and his party lost control of the Senate.
Impeachments were designed as ways to remove corrupt federal officials. That function has mostly gone dormant, replaced by the operations of federal public-integrity law, enforced by the Department of Justice. Each month, DOJ announces actions in some two dozen cases. Recent announcements include the conviction of a former mayor in the federal territory of Guam on extortion changes and a former border officer on bribery charges.
But what impeachment can do in the modern era is send a powerful signal to the public about the gravity of certain cases. When the House impeaches, it declares: We believe we have exited normal politics; we believe we are dealing with a true emergency.
It elevates the president’s alleged abuse over all other congressional business. Impeachment empowers the House to force an issue onto the agenda of the slower-moving Senate. Impeachment changes the calendar of politics. Impeachment concentrates and clarifies issues. Impeachment compels senators to take a public stand one way or the other: convict or acquit.
Because impeachment is such an extraordinary act, it is also profoundly risky to its proponents. If done wrong, it will redound upon the impeachers, as Clinton’s impeachment redounded upon Gingrich and the House Republicans.
In 1998, a substantial majority of the American people rejected the Republican impeachment case against Clinton. After the House approved articles of impeachment, Clinton’s approval jumped to a new high of 73 percent in a CNN/USA Today/Gallup poll, and approval of Republicans tumbled to 31 percent.
Even the fiercest partisans sense those risks. That’s why impeachment does not happen promiscuously. Ronald Reagan was not impeached for Iran-Contra. George W. Bush was not impeached after Democrats won the House and Senate in 2006. Barack Obama was not impeached despite the fervor of the Tea Party Republicans who took the House in 2010 and the Senate in 2014.
The Trump impeachment, by contrast, was supported by a consistent if narrow majority. Seventy percent of Americans condemned Trump’s attempted extortion of Ukraine’s government to aid his reelection. Trump and his supporters hoped and trusted that impeachment would backfire in 2020 as it had in 1998. Pro-Trump pundits confidently predicted that it would backfire. Those pro-Trump hopes were disappointed. The process began and ended with most Americans accepting that Trump had committed impeachable offenses and that he deserved to be removed from office for those offenses.