Today, former President Trump's second impeachment trial will begin in the U.S. Senate. This unprecedented event represents a response by Congress to the unprecedented terrorist attack on the U.S. Capitol on January 6, when Trump infamously incited his MAGA mob to try to forestall the counting of the electoral votes. The one (and only) Article of Impeachment addresses this particular alleged "high crime." So this is not, formally speaking, a continuation of last year's first Trump impeachment event. And yet it is in a sense a resumption of that previous proceeding, its second act of that necessary historical reckoning, a second chance for the country to come to terms with what we as a nation have had to live through these past four years. Tragically, it will likely also have the same conclusion - a colossal failure to come to terms with what has happened to us as a nation.
Over the course of our country's history, eight federal officials have been removed from office after impeachment by the House and trial by the Senate. Three presidents (Andrew Johnson, Bill Clinton, and Donald Trump) have been impeached, but none has ever been convicted. Given the high bar (a 2/3 vote of the Senators) for conviction and given the close partisan divisions in the modern Senate, it may be that no president will ever be convicted and that presidential impeachment will either return to being the dead letter it became in the century after the Johnson impeachment or just the theatrical partisan political performance it became when Clinton was impeached.
That said, unlike the case against Andrew Johnson for breaking a law that should not have been passed, unlike the case against Bill Clinton for lying in response to a question that should not have been asked, and unlike the first case against Trump for an ambiguous off-stage telephone call in the confusing context of international relations, the case this time is clear - the former president's provocative public actions leading to a mob's criminal behavior, all widely watched live at the time and repeatedly seen subsequently. An acquittal, if that is the outcome, will not alter the facts of what happened but will enable alternative interpretations and evaluations of what happened and of the larger Trump phenomenon, a fog of "fake news" to keep clouding our ability to come to terms with our past and move productively forward to some sort of satisfactory national future.
A vote by Senate Republicans to acquit the former president would represent a continued endorsement of the falsehoods about the election, which Tump personally promoted and which continue to dominate Republican party politics, especially in certain states.
Meanwhile the Senate will waste its time today debating the constitutionality of the process. Under normal circumstances, process arguments are an important part of political debate. Process is key to constitutional and democratic governance, and what Trump and his mob are accused of is essentially an attack on the process which is at the heart of constitutional and democratic governance - elections.
Today's process argument, however, is manifestly a distraction - a deliberate avoidance of the substantive issue the Senate is supposed to adjudicate. Admittedly the constitutional text is ambiguous. It neither explicitly authorizes nor explicitly excludes the impeachment and trial of a federal official after he or she has left office. The precedents, however, are less ambiguous.
The famous British impeachment trial of Warren Hastings, accused of misconduct in India, began and continued for several years after Hastings had already returned from India. This trial was going on at the very time the constitution was written and its ratification was being debated. Also at that time, some states explicitly allowed the impeachment and trial of officials after leaving office. Against this background, the federal Constitution's silence on this issue does not support the view that the framers would have excluded this practice. And, of course there is the famous Belknap precedent - Secretary of War William Belknap, who was impeached and tried in 1876, although he had already resigned his office in order to avoid impeachment. The contrary example, of course, would be Nixon in 1974. After Nixon resigned, the House did not move forward with the Articles of Impeachment which the Judiciary committee had already approved. Clearly the country in 1974 was eager to turn the page. That probably was a prudent political decision in 1974, but it does not negate those other precedents. A political choice not to impeach and try a former official does not create a constitutional prohibition against doing so.
Also, thanks to the 22nd Amendment, Nixon was already ineligible to run for president again anyway. So the corollary of conviction in the Senate - disqualification for running for office again - would have been moot. Trump's case is completely different. Trump's alleged offense was far more egregious than anything Nixon did and continues in the anti-constitutional and anti-democratic direction adopted by the contemporary Republican party, which persists as a serious abiding danger to constitutional and democratic governance.