The central institution of the first democracy was the Athenian assembly, where all important civic decisions were put to a vote. And the central tradition of the assembly was that every citizen could speak freely on all such matters. The ancient Greeks even had a word for one who did not participate – an “idiot” – the root of our modern insult.

Modern America is only loosely based on Athenian democracy. We can no longer gather at short notice to vote on a hill in the middle of town. But a belief that every citizen should have an opportunity to speak and be heard remains at the heart of our political tradition.

It plays out even today in New England town meetings, Los Angeles zoning board hearings, and the hundreds of often rowdy town hall events held in home districts when Congress is out of session. And it is reflected in the first amendment principle that the worst kind of censorship is censorship of those who criticize government, because their speech is both essential and vulnerable in a democracy.

On Thursday, a federal court in New York will face a distinctly modern version of this ancient issue. It will consider whether President Trump has the right to block certain individuals from interacting with him on his Twitter account simply because they have said things about him he does not like.

Consider a typical day in political life circa 2018. The president tweets something significant, such as the transgender military ban, the appointment of a new FBI director, or his view on something Congress has done or will do. This information appears instantaneously to his roughly 40 million Twitter followers. Millions of these followers – supporters and opponents – begin to write 280-character reactions at internet speed.

His 40 million followers can see these reactions and in turn react to them. Other Twitter users can react to the reactions to the reactions. The news media reports the original news and often attempts to summarize the public’s online reaction to it. Twitter users react to the news media’s reaction. And on and on it goes.

The specific act being challenged is the president’s right to “block” a Twitter user from following his account – something he does to certain users who have criticized him. One consequence of being “blocked” is that these users are no longer automatically notified when the president tweets.

Another is that other Twitter users – and reporters who follow the president, as virtually all political reporters do – no longer see the blocked users’ tweets in the stream of reactions to the president’s original tweet. While it is true that blocked users can still speak to their own followers, their voices are being excluded from the main current of the political dialogue surrounding the president’s original tweet. In effect, their opinions are relegated to a smaller, slower side channel.

Though our current president is a uniquely polarizing figure, the principle at stake has nothing to do with political ideology. The impact of this ruling will apply to all government officials – Democratic, Republican and otherwise – who have chosen to use social media as an instrument of governing.

The issue is enormously important precisely because so many officials are choosing social media to talk to and hear from their constituents. As the U.S. Supreme Court recognized last summer, social media have become “the modern public square”, and a vast majority of public officials maintain accounts that serve as a forum for speech and debate.

Other politicians also understand that, absent a legal prohibition, they can manipulate social media to make themselves seem more popular by quietly suppressing the speech of their critics. Two years ago, a Democratic county commissioner in Virginia maintained an official Facebook page in which she encouraged county residents to give her feedback. This feedback was visible to her as well as to other Facebook users. But when one constituent posted a negative comment, she deleted it. And by doing so she ensured that other Facebook users would not know the nature of his gripe.

Thankfully, a federal judge ruled last year that her action violated the first amendment. But there is no doubt that politicians across the political spectrum will be watching Thursday’s case to see whether they too should emulate the president’s under-the-radar efforts to suppress critical speech.

Nearly 2,500 years ago, Socrates had this to say about the Athenian assembly: “When the question is an affair of state, then everybody is free to have a say –carpenter, tinker, cobbler, sailor, passenger; rich and poor, high and low – anyone who likes gets up, and no one reproaches him.”

These words resonate even today. He of course knew a world of men orating to a few thousand fellow Greeks. He could never have imagined that same person in front of a screen, logged in to social media, but wrestling with the very same ideas of justice and fairness, war and peace, right and wrong with more than 200 million fellow citizens in a country nearly 3,000 miles wide.

But suppose he were asked to decide tomorrow’s case – is there any doubt whether he would grant them the very same right to speak and be heard on the most important issues of the day?