The opening of impeachment proceedings against President Trump offers a chance to take stock of the state of democracy. Not because of the specific accusations that Mr. Trump faces, but because judging his presidency must necessarily include all the challenges that liberal democracy faces in the 21st century — from distrust of politicians to the power of social media. It is not likely to be pretty.

That this process is taking place in the world’s premier democracy makes it critical for every other land and people. The tumult in Hong Kong, the spread of populism around the world, the agonies over Brexit in Britain, the struggle against corruption in Ukraine, the weight of colonial legacies in Africa — in every corner of the world people are struggling to determine how they should be ruled, and all will be watching how the United States emerges from its trial.

Trust is at the heart of democracy, and a central question in the proceedings will be whether the electorate still believes its representatives and institutions can withstand the acute partisan hostilities of a deeply divided nation. It is fundamental to democracy that elected leaders heed the law and the will of the people; is it certain in the prevailing climate that they will?

Will the free press, now beset by cacophony, echo chambers and fake news, be capable of providing a dispassionate view?