Americans have also seen that, despite the intense pessimism and even disillusionment that many feel about politics, a political party still can show moral courage — regardless of the political costs. The Democrats were told constantly that impeachment would hurt them in November. Mr. Trump himself has boasted that it will, and what’s more he has relished the chance to claim exoneration and to take a victory lap at the same time as Democratic hopefuls began duking it out in earnest in the primaries. The Democrats knew all this, and what’s more, they knew they faced an uphill battle: That’s what the constitutional requirement of a two-thirds Senate majority to convict imposes from the beginning.

But they still did the right thing. They called out impropriety so glaring that it could not be suffered in silence. And they reminded all of us that a political party can pursue what’s right over what’s expedient — and so can a lone politician, as Senator Mitt Romney showed.

Americans saw on vivid display another form of courage: the incredible bravery of public servants who testified before the House of Representatives, the nation and the world — people like Lt. Col. Alexander Vindman and Dr. Fiona Hill. They did so despite the gag orders issued by Mr. Trump to disobey Congress. They did so knowing they’d face death threats. They did so not knowing whether their testimony would yield the president’s impeachment or removal. And they spoke up because they believed in truth as an end in itself.

That’s a reminder, in our disinformation-fueled times, that candor is a value we must recover. And it’s a lesson for the American people that those who serve our government by working long hours for little pay and even less glory aren’t the “deep state” that Mr. Trump denounces but, instead, patriots.

Americans also received a lesson in the critical importance of whistle-blowers in holding our government to account. The role of whistle-blowers is as old as the government itself, dating back to the Continental Congress. But never has their necessity been put on display as clearly as when a courageous whistle-blower filed the complaint that, ultimately, led to the exposure of Mr. Trump’s Ukraine extortion bid.