What if live-streaming required a government permit, and videos could only be broadcast online after a seven-second delay?

What if Facebook, YouTube and Twitter were treated like traditional publishers, expected to vet every post, comment and image before they reached the public? Or like Boeing or Toyota, held responsible for the safety of their products and the harm they cause?

Imagine what the internet would look like if tech executives could be jailed for failing to censor hate and violence.

These are the kinds of proposals under discussion in Australia and New Zealand as politicians in both nations move to address popular outrage over the massacre this month of 50 people at two mosques in Christchurch, New Zealand. The gunman, believed to be an Australian white nationalist, distributed a manifesto online before strea­ming part of the mass shootings on Facebook.

If the two countries move ahead, it could be a watershed moment for the era of global social media. No established democracies have ever come as close to applying such sweeping restrictions on online communication, and the demand for change has both harnessed and amplified rising global frustration with an industry that is still almost entirely shaped by American law and Silicon Valley’s libertarian norms.

“Big social media companies have a responsibility to take every possible action to ensure their technology products are not exploited by murderous terrorists,” Scott Morrison, Australia’s prime minister, said Saturday. “It should not just be a matter of just doing the right thing. It should be the law.”

The push for government intervention — with a bill to be introduced in Australia this week — reflects a surge of anger in countries more open to restrictions on speech than in the United States, and growing impatience with distant companies seen as more worried about their business models than local concerns.

There are precedents for the kinds of regulations under consideration. At one end of the spectrum is China, where the world’s most sophisticated system of internet censorship stifles almost all political debate along with hate speech and pornography — but without preventing the rise of homegrown tech companies making sizable profits.

No one in Australia or New Zealand is suggesting that should be the model. But the other end of the spectrum — the 24/7 bazaar of instant user-generated content — also looks increasingly unacceptable to people in this part of the world.

Prime Minister Jacinda Ardern of New Zealand argues that there must be a middle ground, and that some kind of international consensus is needed to keep the platforms from limiting public protection only to certain countries.

“Ultimately, we can all promote good rules locally, but these platforms are global,” she said Thursday.

Even in the United States, frustration has been building as studies show that social media’s algorithms and design push people further into extremism even as the platforms are protected by the Communications Decency Act, which shields them from liability for the content they host.

Some social media companies are starting to say they are willing to accept more oversight and guidance.

In an op-ed in The Washington Post on Saturday, Mark Zuckerberg, Facebook’s chief executive, called for government help with setting ground rules for harmful online content, election integrity, privacy and data portability.

“It’s impossible to remove all harmful content from the internet, but when people use dozens of different sharing services — all with their own policies and processes — we need a more standardised approach,” he wrote.