Saudi Crown Prince Mohammed bin Salman. (Saudi Press Agency/Handout via Reuters)

ONCE AGAIN, news from Saudi Arabia points toward the old thinking and not the modern society promised by the new crown prince, Mohammed bin Salman. Despite the lofty rhetoric of the crown prince's "Vision 2030" declaration, he increasingly resembles an earlier generation of leaders with authoritarian methods. Saudi Arabia has been, and seems determined to remain, a dungeon for those who want to practice free speech.

The latest evidence is a wide-ranging crackdown on influential clerics, activists, journalists and writers who have been jailed with hardly any public explanation. A Sept. 12 statement by the government's new security agency, set up in July by King Salman bin Abdul Aziz, hinted darkly that the arrests were caused by "foreign parties" that were trying to hurt "the security of the kingdom and its interests, methodology, capabilities and social peace in order to stir up sedition and prejudice national unity. They were neutralized."

This vague language masks the fact that many of those arrested were relatively outspoken online, not secret agents plotting against the kingdom. The exact number of arrests is unknown, but some reports say in the dozens. According to Reuters, the roundups included three clerics who are outside the official religious establishment but have large online followings: Salman al-Awdah, Awad al-Qarni and Ali al-Omary. They have previously criticized the government but have recently stayed quiet or failed to publicly back Saudi policies, including the blockade against Qatar. Human Rights Watch says that Saudi authorities imprisoned Mr. Awdah from 1994 to 1999; since 2011, he "has advocated greater democracy and social tolerance." Mr. Qarni, who has more than 2 million Twitter followers, was banned from tweeting by a court in March that convicted him of jeopardizing public order. He announced the ban on Twitter.

The latest crackdown may reflect Saudi nervousness over any internal dissatisfaction with the kingdom's blockade of Qatar. Some reports say those arrested may have simply failed to speak up loudly enough in support of official Saudi policies. What better way to make the point than to throw them in jail? Writers and activists are also being hauled into prison.

The leaders of Saudi Arabia and its conservative religious establishment are wandering in some earlier century. How to explain the punishment of a severe lashing to blogger Raif Badawi, who has been jailed since 2012 following his online appeal for a more liberal and secular society? His sentence was 10 years in prison and 1,000 lashes, of which he has been given 50, simply for speaking out. How to explain the recent call by the Saudi authorities on the population to use a phone app to inform on anyone who may be considered subversive? This is how Stalin would have used Twitter.

It is easy to issue fancy blueprints for reform, as the crown prince has done. Building a modern, healthy society is a lot harder. It requires, among other things, actions to guarantee basic rights, including the speech of people you don’t agree with.

Read more on this topic:

Jamal Khashoggi: Saudi Arabia wasn’t always this repressive. Now it’s unbearable.

The Post’s View: Saudi Arabia must do something about its barbaric human rights practices

Fareed Zakaria: How Saudi Arabia played Donald Trump

The Post’s View: There’s reason to doubt Saudi Arabia’s charming new crown prince

Charles Krauthammer: Why Middle East peace starts in Saudi Arabia