In the UK taking a private copy of a website is a copyright infringement; doesn't matter if you publish it.

Your idea probably works in USA with Fair Use.

Could you back up this claim? Reading about fair dealing as it is called in UK law [0] leads me to believe otherwise, especially if the copy is used for archival purposes [1].

[0]: https://en.m.wikipedia.org/wiki/Fair_dealing_in_United_Kingd... [1]: https://assets.publishing.service.gov.uk/government/uploads/...

The context was private individuals keeping copies.

There are some exceptions but they're not really pertinent here: You can make a transient copy, eg in order to view a website you might cache something. You can retain a copy of a TV show until you watch it - but can only watch once, and not with company. You can keep copies to facilitate workarounds for disabilities (but again you can use that for retention) ...

Registered archives can keep works so long as they're not accessible by the public.

Your second link, I wasn't totally aware of those changes. However, they don't seem especially pertinent. You're not allowed access to the whole copy of an archive copyright work. Private archives can't keep copies. Public archives can only do so when buying access is not feasible.

The private study requires you to be on a related official course of study, and the works used -- but only accessed in part -- have to be cited in the study results.

So, WBM isn't a UK public library and couldn't copy a UK served website legally for archive. A UK public archive could serve the pages, but only parts of them, and only to people physically in the building.

I think my summary was correct in context; detailed corrections welcome!

Fair Use permits the unlicensed use of copyright-protected works in certain circumstances and takes into account a number of factors--including the amount of the original work that's used. So quoting a paragraph from a blog post to comment on it is almost certainly OK. An entire website? Probably not under most circumstances.