To AC "7 years": A well thought out answer
Thank you for posting your well considered thoughts on the matter.
If I may add:
A lot of the hair-trigger responses to this are from (fellow) Americans, stating their "right to privacy". Actually and accurately, contrary to popular opinion, the American Constitution does NOT guarantee an absolute right to privacy, it guarantees privacy against "unreasonable" intrusions via governmental actions. "Unreasonable" is properly defined as well, being unsubstantiated, without due process, without due cause or failing a legal burden of proof.
So continuing the theme of bursting the bubble on the privacy "absolutists", the United States government went through all the legal processes to show that their request meets a more-than-reasonable burden of proof of why this suspect's privacy needs to be revoked, via assistance in unlocking this very specific and individual smartphone. No grand claims of over-reaching expectations, no FUD thrown around against alleged, yet unknown, perpetrators...no, none of the usual cloak-and-dagger routine regarding why modern electronic privacy needs to be overriden in general. One specific case, with very specific requests for outcomes, against a very specific target.
Exactly what the writers of our laws intended.
In other words, people, get over it. Laws sometimes do exactly what you want they they work as intended, sometimes they work against your specific beliefs but still do what they were intended to do. One case, one phone. No more.