Well at least here in America the government often feels free to ignore international law when it suits them I suspect that since this favors corporate interests, and given the current makeup of the SCOTUS, that the court will defer to Congress on the issue.

It is disturbing that this sort of retroactive change basically throws the copyright status of works into a sort of continued uncertainty. Methinks it is an attack on the very idea of public domain works.

The issue of what the responsibility of sites that host downloads of titles that are in public domain in one country and not in another to prevent downloads by people in the second country is complicated. Is just a disclaimer to the effect of “It's up to you [the downloader] to respect the copyright laws of your country” sufficient if the download site has good reason to suspect that such people are downloading such titles anyway?