I believe there can be different intentions of invoking whataboutism, and under certain context, it can be a perfectly valid informal argument in a debate. The intentions of invoking whataboutism can be

1. Denial of criticism or shifting blame. "Because you had wrongdongs of a similar nature, your criticism of my wrongdoing is null and void." This is the original form of whataboutism, and it's not a legitimate argument.

2. Attack the opponent's double-standard and its authority on being the judge. "Because you had wrongdongs of a similar nature, you are not quantified for judging my wrongdoing." Often the discussion degrades to case (1) and becomes invalid. However, if the existence of wrongdoing is not denied, it can be valid in some cases.

3. Showing additional background of a problem. "Yes, I have wrongdoings. However, you have wrongdoings too, and social studies finds this type of wrongdings is a global problem and widespread in the modern world." This discussion argues the given problem must be examined at a broader context, not as an isolated evil by a single actor. This is a valid argument.

4. Treating the original problem from a different perspective. "If I have wrongdoings and you have wrongdoings, then can it be a possibility that (a) it isn't wrongdoing to begin with, or (b) it's inevitable, or (c) that it's an necessary evil?" Depending on the motivation of the speaker, it can be the same as (1) for denying criticism, but in a honest discussion, this can be valid too.

The "wrongdoings" can be mass surveillance, war crimes, human right abuses, IP theif, and so on. For example, here are some applications of valid "whataboutism" argument. Using mass surveillance as an example.

- "The NSA argues that Government X's foreign surveillance is a threat to the privacy and freedom of Americans. But what about the NSA?! As you see, this is not a real problem but only an excuse for discrediting others politically, and Government X's doing totally fine."

This is an invalid argument and should be frowned upon.

- "The NSA argues that foreign surveillance is a threat to the privacy and freedom of Americans. While it's true, what about the NSA's domestic surveillance that was never really reformed? Thus, the problem of the privacy and freedom of Americans can never be resolved unless both harmful foreign and domestic surveillance have been removed or reformed. If the NSA is only focusing on the first issue, then it's not acting as a fair judge on this problem, and there are reasons to believe the NSA is only acting for its self-interest, not the actual problem."

This can be a valid argument.

- "The NSA argues that foreign surveillance is a threat to the privacy and freedom of Americans. While it's true, what about the NSA's domestic surveillance that was never really reformed? The surveillance capabilities of the NSA is an order of magnitude greater than Foreign Nation X, hence, the threat from the NSA is greater and should be an issue of higher priority."

This is valid argument. Whether the facts and its conclusion is true or false, can be subjected to further debates.

- "The NSA argues that foreign surveillance is a threat to the privacy and freedom of Americans. While it's true, what about the NSA's domestic surveillance that was never really reformed? In addition, the clear evidence showed most liberal democracy governments have unchecked mass surveillance powers on citizens. Hence, it's only a symptom and ultimately, the real problem is ..."

- Liberals: "Unchecked growth of power by secret services authorized by the President, and fueled by its war on terror."

- Libertarian: "Ever-expanding state power in the modern age. "

- Tech-critics: "Dangers enabled by omnipresence of computing and the Internet."

- Infosec researchers: "Disregard of security and privacy in system designs."

These are obviously valid arguments.

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In conclusion, under certain context, whataboutism can be a perfectly valid informal argument in a debate.

> US/ WESTERN COUNTRIES did this before too and therefore no better than China

I honestly believe this can possibly be a valid argument from some perspectives. But I don't want to start any argument, as I'm not interested in this particular debate.

> Somehow US/western countries have to enter the discussion as a bad benchmark...

In some cases, they are good benchmarks. For example, the legal protection of free speech in the United States has flaws, but arguably it's still one of the best in existence globally. Unfortunately, in other cases, they are a bad benchmark, and it's extremely problematic. For example, the government of the USA historically have a record of conduct illegal experiments on human subjects without their knowledge or consent, tries to persuade minority leaders to commit suicide, blatantly lies to Congress about the scope of their illegal programs, and works to overthrow democratically elected governments of other sovereign nations. Then why should a citizen of any nation-state have faith on the United States to implement the Universal Declaration of Human Rights?

The argument above is invalid if I'm using it to shift blame. But it can be valid if it's meant to point out an inadequacy of the US Government or relying superpowers to ensure justice by enforcing International Laws. A hypothetical argument can follow it: If LessWrong's "friendly AI" is feasible and AGI is only 30 years away, it should take control of the world, at least on human rights issues, as soon as possible. Unfortunately, the scenario is unlikely.