As an actual internet lawyer, let me try to explain a bit more. First, it’s waaay too complex to explain all of copyright law here. There are nuances and exceptions and twists to nearly every case. So, don’t consider this as firm legal advice in any particularly situation. It’s just a discussion.
Second, so far as damages: the Copyright Act provides for different types of damages, depending on the circumstances. A person can claim any amount they want in damages–that doesn’t mean they’ll get it.
Third, the basic damages that are allowed are either (1) actual damages and profits of the infringer; or (2) stautory damages.
In most cases of inadvertant copyright infringement on the internet, damages under Option 1 are non-existent. So most opt for statutory damages. Statutory damages provides for damages of $750 to $30,000, in the amount that the court considers “just”.
If the court finds that you committed the infringement willfully, it can boost those damages upwards, but not more than $150,000 per infringement.
However, if the court finds that the infringer didn’t know that what he did was copyright infringement, the court can lower the damages to not less than $200.
So, that’s an enormous scale of potential liability. And there are twists and turns in trying to figure out what any particular case is worth. And “fair use” does not really enter into the description described above.
If you ever have a problem like this, you should really contact your lawyer. Don’t wing it. You’ll probably end up paying more than if you get your lawyer involved at the beginning. This is really an area where someone who works in creative media should have a lawyer on call.