There have been two frustratingly paradoxical truths about the impeachment of President Trump since the process began. The first is that impeachment is necessary. The second is that it will almost certainly end in failure.

That failure was preordained by the results of the 2018 midterm elections: Republicans retained control of the Senate — and, barring some unimaginable major development, will use their majority to defeat any articles of impeachment forwarded from the Democrat-led House of Representatives. "The political reality is difficult," a senior Democrat told The Washington Post this week.

Given this fact, you can understand why some Democrats want to make impeachment a fast and narrowly-focused affair — something to get over with quickly so we can all move on. But taking a narrow approach is wrong. Despite the likelihood of failure, impeachment really is necessary, and the president's wrongdoing is widespread. There are three reasons why the House's impeachment should be of equal breadth.

The first is to shame the "Always Trumpers" of the Congress. Trump has demonstrated a willingness to sell out his country and fellow citizens for personal and political advantage, starting with "Russia, if you're listening" and continuing through "I would like you to do us a favor." And that doesn't count transgressions like profiting from his office, or paying a porn star hush money to keep quiet during the 2016 campaign. At some point the politicians who support him will be judged against the truth of Trump's misdeeds and found wanting. That may happen in the political arena. It may wait for the history books. But Republican denials of presidential wrongdoing — like Sen. John Kennedy's (R-La.) parroting of Russian propaganda, and this week's impeachment report by a House GOP member exonerating Trump — are not built to last. Either way, senators who vote to acquit Trump on impeachment charges will find their reputations and their legacies stained. Taking a broad approach to impeachment forces those senators to own their complicity in Trumpism to the greatest possible extent.

The second reason is that Trump is running for re-election, and the impeachment process is — if nothing else — an excellent way for Democrats to make the case to voters that he lacks the character to occupy the Oval Office. The president is a habitual line-crosser, and his misdeeds in Ukraine are not a one-off. This president lies and cheats on a regular basis, and the House impeachment effort should reflect Trump's sustained lawlessness — if only so voters have a clear picture of his misdeeds.

"One crime of these sorts is enough, but when you have a pattern, it is even stronger," Rep. Pramila Jayapal (D-Wash.) told the Post. That is true in a court of law; it should also be true in political arena.

The third reason? Those aforementioned history books. While Democrats are understandably focused on the here-and-now consequences of their decisions, the truth is that the audience for impeachment includes historians, lawyers, and politicians of future decades who will be looking to this era for guidance and precedent when they inevitably have to face the possibility of their own impeachment process. What Democrats decide matters now, yes, but those decisions could reverberate for decades to come. Democrats talk a lot about "the arc of history" — if they believe their rhetoric, they owe history a relatively complete account of the president's official sins.

Alas, it appears House Speaker Nancy Pelosi (D-Calif.) might prefer to take the fast and narrow path of impeachment — if only to help out moderate congressional Democrats running in districts where Trump remains popular. In September, she reportedly agreed to that approach in a private meeting with members of the House Judiciary Committee, and her previous avoidance of impeachment, before the Ukraine scandal broke, was reportedly rooted in her desire to protect moderates. "I think she wants to keep us as unified as possible," the unidentified senior Democrat told the Post.

But the likely failure of the impeachment process to remove Trump from office doesn't mean the process itself is misguided. Democrats have come this far knowing that ultimate defeat is likely — they might as well make the biggest, boldest, and best case against Trump they possibly can.

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