It's not what the law actually empowers the government to do. The Investigatory Power Act is exactly that - a facility for investigators - mostly the police and intelligence services - to be able to access a person's online data without having to go to that person and seek permission or tell them they're doing so. It doesn't enable the government to do anything. It's a power for law enforcement.They want to be able to spy on people.
That's it. They'll make every excuse under the sun, talking about "protecting the children" or whatnot, but in the end, it's about spying on people.
I'm pissed off about this. There's a good chance it will happen in the US too considering the political situation here.
It also does not enable broad-brush snooping. The law requires a judge to sign off on a warrant for access and the authorities must provide specific reasons for requesting access on a case by case basis. In other words, the person must be a person of interest in a suitably serious incident.
All that being said, I'm also p*ssed off about this and I think it is a very bad move by the UK Government. I think Apple's response is exactly the right one, because it will put the matter between the people and the UK gov. By disabling ADP Apple will have complied with the order, but they won't have weakened the security for anyone outside of the UK.