The law of copyright and by extension all intellectual property law that flows from copyright is founded in the grant, originally by a monarch, but recently of a state or international grouping of states, of a monopoly. Essentially then, copyright law is about imposing a legally and internationally binding monopoly and while it would be easy to assume that such a monopoly was necessarily originally granted to protect and guarantee the welfare of the original author of a work of art (or authorship) that is not in fact the case. Dress it up how you will, the origin of copyright, whence springs all intellectual property law, was instigated to protect the publishers of books. It was nearly 50 years after the enactment of this protection of publishers (The Licensing Act of 1662) that , amid a massive political backlash against monopolistic practices, the Statute of Anne (1709) awarded this purely financial monopoly to authors on the strict understanding that this was a matter of "policy" (a political grant) and not of "natural rights". Under the new version of copyright these rights were granted for 14 years with a possible extension of a further 14 years, after which time these : creative works" would pass into the public domain. There is clearly some legal sleight of hand going on here already: an Statute is enacted to prevent public domain property (it has by definition been made public by the act of publishing) from being treated as thought it were public domain property. However, the saving grace of this early legislation, is that it is only a postponement of genuine public domain treatment. It understands, one might say, what it is doing and sets a termination to the special treatment that it grants. If you will copyright is, at its very legal inception, a political suspension of natural law where once something is in the public domain it is public property.
There are a number of axes along which we can track this politically instigated inversion of or exemption from natural law, and the inevitably increasing "net of protection" that it offers. What we will not do is to detail all of the subsequent legislation that has brought us to today's nonsensical position which is foisted upon us as something both natural and sensible.
The three major axes along which we can plot the extension of copyright are as follows: what works are covered by copyright (remember that in the beginning it was only books); what sorts of rights are granted with the grant of copyright (remember that the monopoly that copyright grants started out as a purely financial right); and the period for which copyright lasts, that is, for how long things that are in the public domain are given exemption from normal public domain treatment.
We shall start with the extensions granted to the duration of copyright and will mention only a few key dates: 1709: 14 years plus another possible 14 years - maximum exemption 28 years 1842 42 years or the lifetime of the "author" plus 7 years - whichever is longer. 1909 56 years. 1911 the lifetime of the "author" plus 50 years 1995 the lifetime of the "author" plus 70 years.
At no point in this not so gradual extension process was there any major objection to the proposed extensions until the Sonny Bono Act in the United States when the period of coverage was brought belatedly into line with the rest of the world and this opposition rallied chiefly around the desire of the lobby group proposing the Act to increase the term to "forever". At this point people started to question whether the suspension of normal public domain treatment could be justified or was desirable. It transpired, that the US constitution, as it currently stands, forbids the grant of copyright without end although, as proponents pointed out at the time, one million years or "forever minus a day" are both finite terms! It must be clear from this most recent development that the beneficiaries of copyright wish to extend copyright protection indefinitely wile there are hopeful signs that some organised opposition to this might yet emerge.