It is a gray area that change interpretation in a highly subjective way. First of all, you said , when you are not buying it in the US, but from outside the US. For example (one of millions), it is not legal to bring most prescription medications into the US in the manner in which they are labled and, if taken to court, the importer would surely lose, but it just isn't going to happen because the quantity of citizenry involved would be heard. It's all numbers! Now, remember when 321 studios was legally selling their product down at Best Buy? Anyone who bought one could own one legally, and still can (Grandfathered), ahhhhh but using it...that's not legal. Get it?
US laws kind of contradict each other. There's the fair use act which entitles you to a backup copy of anything that you own, but then there's another that prohibits bypassing encrytpion placed on the media you own..... But with the big checkbooks of the movie and music industries, the fair use act is not holding up so well......
but to back up your own home videos, you wouldn't need to get around the encryption cuz on homemade movies there isn't any.
Now, by golly there's a thought! What if you encrypted your home movies with CSS to protect them, then wanted to make a copy of one and so you decrypted it...somebody call Hollywood.
> so if i buy it and i live in the US and use it to backup lets say my home video's its totally legal? < Absolutely, yes.