Correct. The carrier controls that SE, in this case Google is making it easier for people to work with their own SE by giving Android ability to talk to it. Yo

Correct. The carrier controls that SE, in this case Google is making it easier for people to work with their own SE by giving Android ability to talk to it. You can/could do the same thing with carrier's SIM actually. All SEs run something called Java Card, which is a standard API you can write against (in Java). Each app gets it's own isolated part of the secure storage, and runs in complete sandbox from other apps and can communicate to apps on the host device. The chip inside the SIM and the SDCard are pretty much the same. Just different packaging.