What is the real reason Apple won't unlock the San Bernardino killer's iPhone?

Apple won’t unlock a terrorist’s phone. Nobody disputes that — though arguments vary wildly over why exactly it won’t.

While Apple looked to present the fight as being over security and privacy, some have accused it of being a question of profits. The company needs people to believe its phones are safe because only then will people buy them.

It’s fairly clear that unlocking the phone in this instance isn’t too painful for Apple — Tim Cook said in his letter to customers that the company had been helping the FBI get into parts of the phone, and that it would do what it could without weakening security.

What are the real reasons that Apple is fighting the US government?

This has been a large part of Apple’s argument. If it breaks the security on this particular phone, it will be doing something that will be dangerous since it means that all phones will become potentially breakable.

The same thing applies elsewhere. The UK Investigatory Powers Bill, for instance, looks as if it could require companies to weaken encryption so that spies can more easily read messages.

But Apple argues that it would need to build an entirely new version of the operating system to do that. And in doing so the weaknesses that built into the phone will be exploitable by bad as well as good guys.

The law works on a system of precedent: if Apple is forced to unlock this phone, then it will mean that the law allows for phones to be unlocked. From there, judges and politicians will be able to ask of Apple that it unlocks its devices — and lean on this same ruling every time it wants to do so, even in more questionable situations than that of the San Bernardino shooting.

It’s been pointed out by a lot of people that resisting the order is of financial help to Apple as well as being a matter of principle. The company depends on people thinking its phones and the things on them are secure — otherwise, presumably, most people wouldn’t use them or limit what they have on them — and so making a show of resisting the order helps secure that.

This was undoubtedly part of Apple’s thinking, and it would be unthinkable that it would have made such a show of resisting without considering the effect on its bottom line. But it’s a case where what appears to be Apple’s genuine commitment to a principle lines up with what good publicity.

And it’s worth remembering that not all of the publicity is good — it’s entirely possible that it would have been better for Apple to stay quiet, fulfil the FBI’s request, and never tell anyone. The company has been criticised by everyone from the Financial Times to Donald Trump, and the headline that Apple is “keeping the US government from looking at a terrorist’s messages” could easily turn a number of people off.

Tim Cook has made clear that he doesn't think that Apple should only be doing things for financial reasons. In 2014, it was reported that an angry Mr Cook respnded to investors, arguing that people who believed that Apple should only be doing things to make money "should get out of this stock".

It is, as you might expect, most likely to be a bit of everything. Apple built its phones to be secure because it makes them sell better, and it keeps things safe; Apple wants to ensure that people keep buying phones, and that they continue to be safe.

But that doesn’t mean that Apple isn’t philosophically committed to keeping its phones secure, too. The company has done a lot in the realm of user privacy — not just encryption, but also not selling on users’ data as competitors do — and while that has helped its marketing, it also only managed to market itself that way because it was committed to that principle.