Originally Posted by
SeriouslyLost
I've never yet had bags checked through entering the US regardless of single or multiple tickets. It's always been the case I've had to, err, pick up my cases, clear US Customs and then re-check them. I've always just assumed it was part of the US security theatre routine.
It's nothing to do with security - just Customs. Same as it is in Australia and many other countries.
What most US airports do well (unlike Australia!) is that they will have a bag drop area immediately after Customs. Presuming your bags are already tagged (aka "checked through") you simple need to drop the bags on the belt and you're done. In most places the process is the same regardless of what airline your next flight is on. There's no need to actually go through any form of "check-in" process.
It's the difference between carrying your bags at most a few hundred metres from the luggage belt to the re-check area (via customs) to potentially having to take them on a bus/train to another terminal and then line up to check-in.