and that US actions toward its minorities might be similar, does that make whatever China is actually doing worth defending though?

From my point of view, what the USA is doing is not similar, because the USA focuses on punishment and, if that doesn't work, destruction of the offending group. The Chinese approach was to expand (access to) education, provide vocational training, and ease other difficulties the group was experiencing that contributing to the root cause of the terrorism. If the Chinese approach had been similar to the USA's approach, they wouldn't have put money and time and effort in to rehabilitating. Rehabilitation is a much preferred solution than punishment and destruction.

Also, the Chinese approach worked: treating people like humans and working to rehabilitate resolved the terrorism issue.

The UN Human Rights Council in 2019 published a report praising China's handling of the situation, noting how it was human-centered:

We commend China’s remarkable achievements in the field of human rights by adhering to the people-centered development philosophy and protecting and promoting human rights through development. We also appreciate China’s contributions to the international human rights cause. We take note that terrorism, separatism and religious extremism has caused enormous damage to people of all ethnic groups in Xinjiang, which has seriously infringed upon human rights, including right to life, health and development. Faced with the grave challenge of terrorism and extremism, China has undertaken a series of counter-terrorism and deradicalization measures in Xinjiang, including setting up vocational education and training centers. Now safety and security has returned to Xinjiang and the fundamental human rights of people of all ethnic groups there are safeguarded. The past three consecutive years has seen not a single terrorist attack in Xinjiang and people there enjoy a stronger sense of happiness, fulfillment and security. We note with appreciation that human rights are respected and protected in China in the process of counter-terrorism and deradicalization.

(emphasis mine) This is from UN Document "A/HRC/41/G/17".

Personally, I'm glad you're asking questions and being upfront about your uncertainty.

I'll let others give the details on Xinjiang but I'll say, briefly, that China's work in eradicating terrorism and improving the standard of living for Uighur Muslims and others in the region are commendable. Not only should this be defended, it should be praised and used as a model elsewhere.

The answer as to whether I/we agree on that definition depends on a class analysis and also relates to your question about authoritarianism, which I'll answer first.

The class war broke out a couple of thousand years ago. It has been authoritarian since the beginning. Under the current system, dissent will be met by armed police and military force, made lawful by legislation and supported by the judiciary; the bourgeoisie will deploy this force at the first sign of any threat to its power. Peaceful protestors against fossil fuels, wars, and the regression of women's health rights will be locked in prison, for example.

Given these observations, the only options are: (i) ending authoritarianism (which is one of the ultimate goals of communism); and (ii) continuing authoritarianism in (a) the same form (which means continuing with capitalism) or (b) a different form (which Marxists think of as necessary in the transition away from capitalism).

If we then change the question to, 'Do you accept that socialists must be authoritarian?' Yes: https://www.marxists.org/archive/marx/works/1872/10/authority.htm. If the workers gain control of the means of production, the only way they will maintain control is by exercising a similar kind of legislative, executive, and judicial authority as is currently wielded by bourgeois states. I also can't see how it's possible to gain control of those means in the first place, except by being authoritarian.

Back to the definition of 'tankie'. First thing to note is that I've never called myself a tankie except in jest. I have no idea what critics mean by it unless it's a pejorative term for a Marxist. In which case, the definition, 'Defending the use of force against civilians expressing disagreement over their government’s decisions peacefully' is just absurd.

If tankie is simply shorthand for 'Marxist', then it refers to 'historical materialists'. Historical materialism is a way of looking at the world that treats everything as a process, a relation, as historically contingent. We can go into this if you wish.

That's not to say I don't have anything in response to:

Defending the use of force against civilians expressing disagreement over their government’s decisions peacefully?

But my response is to ask a few questions:

1. Are there examples of liberal democracies using 'force against civilians expressing disagreement over their government’s decisions peacefully'?
2. If so, does this make liberals (who by definition support liberal democracies) 'tankies'?
3. What is meant by 'peacefully'?
4. What is meant by 'government'?
5. What is meant by 'use of force'?
6. What is meant by 'civilians'?
7. What is meant by 'disagreement'?
8. What is meant by 'defending'?
9. What is meant by 'expressing'?

I doubt very much that (m)any Marxists would support bourgeois states' use of force against peaceful anti-war and climate change activists. But the same people might support a socialist state suppressing pro-war, pro-fossil fuel, or pro-capitalist activists who are known to be supported by a foreign imperialist state's secret service.

Much of it comes down to class position. Marxists understand history as class struggle. It doesn't make much sense for a Marxist to treat individuals separate from a class analysis. So the individual 'peaceful' 'civilian' 'expressing' 'disagreement' is actually entwined in a much larger class struggle and is part of one class or another, which changes the dynamic of the question.

Feel free to come back with further questions.

The main reason why I'm so vehemently against the Uyghur genocide narrative is that it's plainly meant to turn the people of the US against China in preparation for a war. You're telling me that the country responsible for a million+ dead Muslim civilians in Iraq gives half a shit about Muslims in China? C'mon. That's obviously bullshit and there must be some other reason why we're going on about it.

Looking into it more the reasons are to destabilize the region to impede the Belt and Road Initiative and to prepare for war with China. I just don't think the US should be involved in the region, full stop, and therefore I am opposed to the US narrative on happenings in Xinjiang. There's no need for overanalysis or splitting hairs on the definition of genocide here.

In every case when a state is saying something you must ask, why are they saying that?

As for use of force against civilian protestors: If these protestors are foreign agents of the US, they should of course be cracked down on so long as doing so doesn't grow popular support for the movement. The US and the "international community" commits acts of color revolution and sabotage at every opportunity and socialist states must defend themselves against these acts or face collapse. Genuine protests with the will of the common people behind them should be listened to and taken into account in policymaking.

Defending against accusations of genocide? Yes. Although the phrasing can sound odd because it is largely a fabricated narrative. I think most here would support China's actions as a deradicalization program against religious extremism, especially compared to the US solution in neighboring Afghanistan and Iraq.

Tankie is really just used as an insult against "communists I don't like." It's not like it has any theoretical depth. It has an etymology related to the definition they gave you but that only has so much influence on its use.

Class war is the ongoing state of things. Like infation and rent hikes. If a revoluton broke out, of course it would be authoritarian. And the resulting state would probably take an extremely cautious siege socialism approach if it wanted to survive, so yes it would probably be authoritarian. But choosing to not be authoritarian is really just willfully ceding power to the previous ruling class who are not going to give up their position peacefully, even after a revolution. Think about the media narrative and war hawk stances against Cuba, the DPRK, the PRC. Now imagine that but applied to a newly founded socialist republic.

Defending the use of force against civilians expressing disagreement over their government’s decisions peacefully?

Very ironic, since the phrase "Tankie" was coined to describe socialists who were in favor of "sending in the tanks" when Hungarian fascists attempted a coup in 1956. The "peaceful civilians" in question broke convicted Nazis out of prison, formed lynch mobs, and went around marking the front doors of Jews and communists for extermination before they were finally stopped.