I checked the US costums website and they had a FAQ with hamsters, and it said that if the hamster seems in good health, it can go through.
They have an email question system, so I sent a more precise question on rats, I'll tell you what they answer!
However it would only be possible by car if they say it's ok because the bus company (greyhound) doesn't allow any animals on board , and the train (amtrak) only allows animals for special needs people (maybe the bus does that too).
Diamond I thought about just bringing her, but like chinchi said, it's ridiculous to risk losing her, I can easily get friends to keep her for me, but it's just that I'd rather take her with me if I can so I know she's getting outside time enough!
Since I got robbed i can't afford to get a second rat in case I need to bring both to the vet (i refuse to have pets i can't bring to the vet...) so I'll wait till i can get a part time job that coincides with my school. For now louna has to stay a lone rat
so she has to be out of her cage as much as possible to compensate in my eyes, and get lots of attention!