"Internet Archive's actions are almost certainly not lawful<...>"This raises an even more important point: what do citizens do when laws are enacted that do not have acceptance or are not considered as legitimate by a majority of citizens?
This is why enacting treaties such as the Berne Conventions (WIPO etc) are so damned dangerous. By their intrinsic nature, it's quite possible for small non-representative groups to have an international treaty enacted/agreed to by all 'member' states without all states even knowing the full ramifications of the said treaty are—they're forced to sign for some other 'quid pro quo' or special trade-off deal etc. Let's face it, this is how Victor Hugo and his cronies 'won' the copyright war (one must concede they played a masterful game and won outright).
As their champions know full well, once a treaty such as the Berne Convention is up and running then it is almost impossible to change it let alone have it abolished. Savvy operators such as Victor Hugo knew this from the very beginning before even entering the campaign (as that's how international politics works). This is especially the case when treaties are about matters that are not considered truly high stakes such as nuclear disarmament.
It depends on one's political stance how one views treaties that have little or no legitimacy among a majority of citizens. Some would argue that they are technically lawful and should be obeyed, others would say they're morally corrupt and thus should be disobeyed or ignored.
It's this dichotomy that's at the center of Copyright Law/Treaties today. The very fact that the 'Big Boys' consider this treaty little more than a nuisance—just noise in the grand scheme of things—is why disputes over Copyright won't end anytime soon.
The fact that such flaky and unrepresentative international treaties can exist says more about the unhealthy state of the laws in each member state. In recent decades we've all witnessed citizens' growing disrespect for institutions such as democracy and its democratic processes. It doesn't take much imagination to realize that all these problems are interrelated.
When systems of law break down or lose their legitimacy what does one do? Again, this depends on one's politics and worldview. At one end there's disorder and anarchy, at the other one becomes subservient to a corrupt state.
Take your choice. What I know is that I certainly don't want anarchy or revolution as many people die and in the long run they end up benefiting no one. Nor do I want to be subservient to law that's been 'legitimized' by corrupt non-repetitiveness processes.