Your bonus word of the week is tu quoque.
English, as someone remarked is a Germanic language trying to pass itself off as a Romance language. This identity dysphoria is a source of many of its confusions, as well as of its richness.
Sometimes its borrowings are wholesale appropriations, as with the Latin tu quoque, the term for a form of retort that accuses the accuser of doing the same thing. The literal Latin meaning is "you also."
Though the tu quoque (pronounced "too KWOH-kway) argument is generally considered a logical fallacy, it can be valid in pointing out an opponent's genuine inconsistency. For example, a liberal asserting that Judge Brett Kavanaugh lied in testimony to the Senate Judiciary Committee and should be rejected for the Supreme Court may be met by a conservative asserting that Bill Clinton should have been removed from office for lying about his affair with Monica Lewinsky in sworn testimony.
A fair point. (And indeed, the right thing would have been for President Clinton to resign over having committed perjury; there was a competent vice president serving at the time.)
But more often the tu quoque response is merely an example of whataboutism, an attempt to dismiss an opponent's point with an accusation of hypocrisy but without directly addressing or disproving their argument. It is a transparent attempt to deflect attention from an accusation, to derail an argument. The particular spin of whataboutisn, Merriam-Webster explains, lies in "directing its energies into establishing an equivalence between two or more disparate actions, thereby defaming the accuser with the insinuation that their priorities are backwards."
These days, for example, any "What about Hillary's emails?" or "What about Benghazi?" is mere shouting without even a pretense of argument.
Example: From Michael R. Marrus, "The Nuremberg Trial: Fifty years later" in The American Scholar, Autumn 1997: "The most conventional of these, Count Three, was War Crimes, based largely on the Hague and Geneva Conventions. About the legality of these charges, which applied to atrocities committed against both military personnel and civilians, there was little dispute. And there has been little challenge since, save, as we shall see, over the question of tu quoque ('you did it too')."