Fair enough and I would not want to live or write in a world where ideas were copyrightable. I'd would be even tougher to be new writer!
But you did get to the crux of my question and I thank you. Given that one can copyright exact words, or at least a certain number of exact words I presume, does anyone know at what point a character or developed plot is protected? Can the orphaned boy be named Harry Porter? If every year at his school brings a new defense against the dark arts teacher -- has a line been crossed?
Please understand that this is just intellectual curiosity (I do not expect to steal or be stolen from), but because the issue of copyright came up it did make me curious about where the line is.
Ideas are generally not copyrightable or otherwise protectable. Titles and character names are too short to cover under copyright, but copyright isn't the only type of intellectual property protection.
Star Wars, Harry Potter, Star Trek, Raiders of The Lost Ark, all those big blockbuster movie titles are protected under trademark, a short one or few-word phrase that others can't use without permission. The title and names such as "Han Solo" and "Chewbacca" are registered, and are effectively brand names - no one else can use those names for their own characters, whether it's in their own novel or for action figures.
When a movie or book gets popular (or if the movie has a large budget and they market it enough to make it popular, as in sequels and such), the title and major characters' names are surely protected by trademark and you can't publish a story using them. If it's a movie most people have never heard of, chances are the title and MC's are NOT protected by trademark, but then no one would want to use them in their book anyway.
Trademarks in the USA are handled by the Patent and Trademark Office:
http://www.uspto.gov/
But would the fact that I have Canadian copyright protection do me any good if the book was published in the US and plagiarized by someone in Romania?
This would be covered in the Berne Convention:
http://en.wikipedia.org/wiki/Berne_Convention_for_the_Protection_of_Literary_and_Artistic_Works
The USA and Canada are members, and from this list so is Romania:
http://www.wipo.int/members/en/
But also, international copyright is like domestic copyright in that it doesn't make infringers stop, it only gives you the right to sue an infringer. You still have to hire a lawyer who writes a nastygram to tell them to stop, and if/when they don't the lawyer then takes the case to court, and if it's international, that adds to the expense. It may not be worth it unless your book is selling well, AND the infringer has money and can be easily chased down.