Blackstone was talking in the abstract. Clearly Franklin was too considering many of the other things he's known for saying.
You are wrong. Punishment is when you impose a penalty as retribution for an offense.
I understand why you think I'm wrong, but I hope you understand why I think that way. We can disagree, and that is fine, but let's not act as if there are objective answers in social constructs.
Because, I do think punishment is an imposed penalty. In this case, on your rights. Rights are abstract, and these are not binary nor clearly discrete. House arrest is not jail, nor are fines. But as communicated to you elsewhere, the 4th amendment is about ensuring friction for removing someone's negative rights.
But I disagree that punishment is imposed as a penalty as retribution for an offense. You imply that this requires an actual offense to have been made. I assure you that punishment can be imposed for any arbitrary reason. I can also assure you that punishment is a spectrum, from extremely minor (as I think we'd agree is in this case) and extremely harsh.
We're following the ideas of Blackstone and subsequently those that founded the country in question. The US was founded under the idea that natural (or negative) rights were exceptionally important[0] AND that the government should be treated as an adversary (since this is the main body that could impinge upon natural rights). The idea isn't that natural rights can't be violated for any reason, but rather that there needs be friction at every step, including the smallest amount. The reasoning being that they were intimately familiar with power creep.
So yeah, semantics, but literally the semantics that we the topic of overthrowing an entire government for. ¯\_(ツ)_/¯
[0] So much so that they appear in the second paragraph of the Declaration of Independence[1] (which goes on essentially ranting about this topic)
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, --That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.
[1] https://www.archives.gov/founding-docs/declaration-transcrip...
if your entire family is "interrogated" over some crime you did not do, is that "punishment"? Maybe not legally, but it's a stressful time that may or may not cause strains on your relationship between your spouse and kids. And it's not like this is an investigator coming in for tea and asking a few questions, either.
morally, it would indeed be a punishment. There is now a bunch of nervous sentiment among your family for no reason, all because you were at the wrong place at the wrong time. Or if we want to be frank, you looked the wrong race at the wrong place at the wrong time.