So, viewing a movie on Youtube existentially causes copies to be present on your computer. Are we to assume that all viewers of websites, online video, or streaming music services are copyright infringers making illegal copies all over the place?
Not all viewers, but a hell of a lot of them.
Here's an excerpt from Intellectual Reserve v. Utah Lighthouse Ministry, 75 F. Supp. 2d 1290 (D. Utah 1999):
Do those who browse the websites infringe plaintiff's copyright?
The first question, then, is whether those who browse any of the three infringing websites are infringing plaintiff's copyright. Central to this inquiry is whether the persons browsing are merely viewing the Handbook (which is not a copyright infringement), or whether they are making a copy of the Handbook (which is a copyright infringement). See 17 U.S.C. 106.
"Copy" is defined in the Copyright Act as: "material objects . . . in which a work is fixed by any method now known or later developed, and from which the work can be perceived, reproduced, or otherwise communicated, either directly or with the aid of a machine or device." 17 U.S.C. 101. "A work is fixed' . . . when its . . . sufficiently permanent or stable to permit it to be perceived, reproduced, or otherwise communicated for a period of more than transitory duration." Id.
When a person browses a website, and by so doing displays the Handbook, a copy of the Handbook is made in the computer's random access memory (RAM), to permit viewing of the material. And in making a copy, even a temporary one, the person who browsed infringes the copyright. n5 See MAI Systems Corp. v. Peak Computer, Inc., 991 F.2d 511, 518 (9th Cir. 1993) (holding that when material is transferred to a computer's RAM, copying has occurred; in the absence of ownership of the copyright or express permission by licence, such an act constitutes copyright infringement); Marobie-Fl., Inc. v. National Ass'n of Fire Equip. Distrib., 983 F. Supp. 1167, 1179 (N.D. Ill. 1997) (noting that liability for copyright infringement is with the persons who cause the display or distribution of the infringing material onto their computer); see also Nimmer on Copyright 8.08(A)(1) (stating that the infringing act of copying may occur from "loading the copyrighted material . . . into the computer's random access memory (RAM)"). Additionally, a person making a printout or re-posting a copy of the Handbook on another website would infringe plaintiff's copyright.
Footnote n5: Although this seems harsh, the Copyright Act has provided a safeguard for innocent infringers. Where the infringer "was not aware and had no reason to believe that his or her acts constituted an infringement of copyright, the court in its discretion may reduce the award of statutory damages. . . ." 17 U.S.C. 504(c)(2).
More importantly, wouldn't that make the internet a device primarily intended to enable copyright violations and illegal to manufacture, import or posses under copyright law?
No. Just because it's commonplace doesn't mean that the Internet is intended to enable infringements. The Sony precedent and the DMCA safeharbor both work to protect the continued existence of the Internet, despite widescale infringement. Remember, the basic rule of Sony is this: "[T]he sale of copying equipment, like the sale of other articles of commerce, does not constitute contributory infringement if the product is widely used for legitimate, unobjectionable purposes. Indeed, it need merely be capable of substantial noninfringing uses."
But just because ISPs are not obligated to dismantle the Internet doesn't help individual infringers.