There are two essential reasons for this. First, to create a precedent that condemns his dictatorial methods and makes clear that violent insurrection will never be tolerated. Second, to disqualify Trump from holding public office again. As the US needs to vaccinate itself from COVID-19, so it needs to vaccinate itself from Trumpism.

The history of impeachment, however, suggests this will be difficult. Taking British law as a precedent, the framers of the US constitution included the power to impeach to convict public officials guilty of "treason, bribery, or other high crimes and misdemeanors". Thus far, eight judges have been removed from office after impeachment.

Since the American Revolution, the House of Representatives has impeached three of 45 presidents: Andrew Johnson (1868), Bill Clinton (1998), and Donald Trump (2019). Only one has been impeached twice: Trump. No president, however, has been forced out of office by the subsequent Senate trial.

After the Civil War, the House impeached Johnson. Radical Republicans detested his leniency toward the defeated Confederates, so when he unconstitutionally sacked the Secretary of War, Edwin M. Stanton, they leapt to impeach. Johnson's presidency survived when the Senate acquitted him by one vote.

Richard Nixon jumped before being pushed. He resigned in 1974 before certain impeachment over his covering up of the burglary of the Democratic Party headquarters in the Watergate building. Nixon's successor, Gerald Ford, pardoned him for any crimes, including tax evasion, he may have committed. Ford argued that, having suffered through an era that included the assassination of the Kennedy brothers and Martin Luther King jnr, urban uprisings, and the catastrophic Vietnam War, the nation could endure no more. Maybe so, yet he failed to set a precedent that made it clear that presidents are not above the law. Ford paid a price; his popularity immediately plummeted.

Clinton committed perjury, lying under oath about having oral sex. The Senate acquitted him. In 2020, it too acquitted Trump after he attempted to blackmail the President of Ukraine into finding compromising material on Joe Biden's family. His purpose then, as now, was to interfere in the election.

If a "successful" impeachment is so hard, why try again?

Because all other options have failed. Trump did not resign like Nixon, and Vice-President Pence, the most supine vice-president in decades, did not use the 25th amendment to remove and replace Trump. Congress could censure Trump, but that would be a toothless gesture. The only political action with consequences is impeachment and conviction.

The House of Representatives found that Trump incited a riotous insurrection, something every member of Congress witnessed. Trump stood before an armed and furious mob on the day election results were to be certified. He told the rioters that the 2020 election was fraudulent, even though Biden fairly won 81 million votes to Trump's 74 million. He told the mob to go to Congress to intimidate the Vice-President and the Republican Party into challenging the election results. "You'll never take back our country with weakness. You have to show strength," he said. From the same stage, Trump's lawyer, Rudy Giuliani, exhorted the mob to wage "trial by combat." Given its cue, the mob stormed the Capitol building. Credible reports indicate it threatened lives of Vice-President Pence and the Speaker of the House, Nancy Pelosi. Five people died.

That is not all. Trump also pressured officials in Georgia to overturn the presidential election result. His corruption is on tape, and is impeachable by itself. Moreover, he has spent two months seeking to reverse a fair election. He even discredited it before election day, casting doubt on legal mail-in ballots, used in record numbers due to a pandemic that has killed over 370,000 Americans. Trump has no evidence of a fraudulent election, but persists in undermining democracy. This is not to mention his threat to lock up his opponent in 2016.

A Senate failure to convict Trump will signal that all of the above is tolerable and therefore repeatable. Instead, for the first time in US history, the Senate must uphold an impeachment.

READ MORE:

Incoming Majority Leader, Democrat Chuck Schumer, will have to balance the trial with Biden's legislative agenda. The Senate could start the trial on Biden's inauguration day, but will likely wait 100 days. When newly elected senators Jon Ossoff and Raphael Warnock join the Senate by January 22, the Senate will be split evenly, 50-50, along party lines.

Seventeen Republicans will have to vote "yea" to seal Trump's fate. Outgoing Senate Majority Leader Mitch McConnell thinks Trump committed serious enough offences to warrant impeachment. So, too, Republican Senator Lisa Murkowski. They appear to be in a minority in the Republican Party, yet there are advantages for the party in supporting impeachment. If it has the will, it can break free of the Trump personality cult - and some senators eyeing a presidential campaign in 2024 would do better without him. The remaining issue is that they reportedly fear retaliation.

A failed impeachment might go both ways for the Democrats. They will be accused of doing the same thing as Trump (not accepting his 2016 victory) and of stoking partisanship. There is also the risk that if an election is genuinely fraudulent in the future, it will be harder to prove. But the Democrats will have at least attempted to stop the corruption of democracy.

The pragmatic fortune of either party is not, however, the main issue. Rather, it is this: a democracy should not tolerate violent insurrection, especially by a legitimately defeated political candidate. The defender and embodiment of that democracy, the Congress, must make that clear. The House has done its work. Now, it is over to the Senate.