If the Government privately tells you....we need a back door to everything and keep your mouth shut...you will give them what they want. Anyone that thinks that they can't do that is kidding themselves...
Our government is corrupt and run by money. The businesses control the government, not the other way around.
When a business the size of Apple tells the government that they won't build a back door, they aren't going to build a back door.
Other companies might be small enough, or care little enough, that they'll comply with what the government tells them to, but Apple is neither little nor do they not care.
If Apple has a backdoor, it'll be found soon and Apple's support from privacy advocates will evaporate overnight.
But I don't think Apple has a backdoor, because the director of the NSA won't stop publically bitching about how impossible it is to get data from Apple. Plus it wasn't found when everyone else's backdoors were found.