you used to be able to use transit lounges en route through the USA to somewhere else; I think stopping it was a post-9/11 thing. Crazy, since if you are indeed a terrorist you are now loose in the USA with your deadly luggage. What dzug says applies to international flights, or at least it did last time I stopped in LA en route to Auckland: go through immigration, pick up luggage, rush upstairs, check in luggage, go through immigration. All to re-catch a plane that had merely touched down to swap crews and be hoovered.