Congress is vested with the power to provide to authors and inventors, for limited times, the rights to control the distribution and commercial copying of their intellectual property. Copyright law (USSC 17) embodies these rights. The rights granted by this section of the constitution have been bound and refined through congressional acts, most recently with chapter 12 of the copyright code, commonly called the DMCA.

Where congress has exceeded its constitutional power, the judicial system (usually) puts the situation right again.

In the end, the "exclusive right" mentioned section 8 of article 1 is not cut and dry. Beset by the first amendment and the phrase "promote the progress of science and useful arts," intellectual property holders' rights are limited by fair-use defenses popularized by the judicial system and eventually codified in chapter 1 of the copyright code. When determining the validity of a fair use defense, the judicial system will consider:

1. the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
2. the nature of the copyrighted work;
3. the amount and substantiality of the portion used in relation to the copy righted work as a whole;and
4. the effect of the use upon the potential market for or value of the copy righted work.

Chapter 10, Subchapter D, §1008
No action may be brought under this title alleging infringement of copyright based on the manufacture,
importation, or distribution of a digital audio recording device, a digital audio recording medium,
an analog recording device,or an analog recording medium,or based on the noncommercial use by a
consumer of such a device or medium for making digital musical recordings or analog musical recordings.

This is a specific fair use that congress says is OK, the general case is still left for the courts. Congress has handed you the right to rip your CDs for personal use in no uncertain terms. Your rights to do the same to do every other copyrighted work, until the DMCA, were rarely questioned. (Don't worry, for the moment,  that we 'consumers' are shielded from litigation because digital audio recording device manufacturers pay a fee to "interested copyright parties." Just don't forget to submit your claim to that fee in the first two months of every calendar year pursuant to Subchapter C, §1007.)

The Digital Millennium Copyright Act, passed in 1998, is congress' latest attempt to broaden the rights accorded to copyright holders after enjoying lobbying by collusive copyright oligopolies like the motion picture and recording industries. Until CD players became household appliances, copyrighted works were generally distributed in analog form. Copy protection was often cumbersome (remember irreproducible red pages in computer software manuals with copy protection codes, or ever hear of Macrovision?) and copyright owners simply lived with the fact that people would make "unauthorized" reproductions of their works. Most of them would be legal under chapters 1 or 10, anyway.

With the advent of digital distribution, the copyright conglomerates (think AOL-Time/Warner, Disney, Fox and Sony) spied a revenue opportunity. They could restrict through technical means what congress and the judicial system had long denied them through legal means. They needed a little help from congress, and got the DMCA passed, making it illegal to circumvent access controls put on copyrighted works. All that remained was to distribute digital works protected by an access control measure.
 

• Copyright Law (PDF) (HTML)
• Chapter 1 (HTML)
• Chapter 10 (PDF) (HTML)
• Chapter 12 (PDF)  (HTML)
• The Anti-Circumvention Rulemaking
• The US Constitution
• Congressional Research Service interpretations of for the Library of Congress:
• The First Amendment
• The Copyright Clause