The state should be able to get a warrant to intercept communications for reasonable cause, and the accused should be able to litigate the validity of the search.
Unfortunately, in the world of crypto, if the state can intercept communications, then it's equally possible that a determined attacker can. Encryption either works for everyone, or it doesn't.
Governments are more powerful actors on this playing field, but they are far from the only ones on the field.
A warrant doesn't expose something your saying to the government, it exposes what you're saying to anyone who might be listening.
We're not talking the equivalent of handing some documents over to the police, we're saying the police are ordering us to stick the documents to the window of our house so that they can see them.
You may notice that I didn’t include any advocacy for NSL in my comment.
Pretending that technology is infallible is a defect equally as bad as NSL with respect to the rule of law.
Obviously no complex IT system is infallible, and now we have a situation that with no legal remedy, the police and intelligence services are compromising or allowing latent defects to remain in order to fulfill their missions.
You never hear about law enforcement concerns with respect to iMessage or Signal, so it is likely that whatever security you think you have from the state is not meaningfully there.
Plenty of other countries have similar mechanisms, where the user is also not informed (because of a court order or similar). The US is certainly not the only culprit here, although they may or may not be the worst.
Australian resident with a UK passport checking in here. Australian's are fucked too. And we pretty much copy/pasted our new laws from the UK ones, so UK residents are as well. If Canada/New Zealand have not already passed equivalent laws or are not in the process of doing so, my paranoia about Five Eyes might be a little miscalibrated. But realistically, I suspect its more likely that I'm not paranoid enough, rather than too paranoid...
The state should be able to get a warrant to intercept communications for reasonable cause, and the accused should be able to litigate the validity of the search.