I don't think you get it.. Pretty clear
The Fourth Amendment of the U.S. Constitutionprovides, "[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."
No, I get it perfectly. You don't.
Warrants are all well and good. But this is a different situation.
The government getting a warrant to search someone's house doesn't put every other home owner at risk or decrease the security of those other homeowners' properties.
This would, and that's the difference many people can't grasp.
It is mathematically impossible to build a cryptographic system that would let the government in with a warrant but not expose everyone else in the process.
So going back to the 4th amendment, if I have done nothing wrong, and there are no warrants against me, I have the right to security. So do the 750+ million other iOS users who are law abiding. The government simply does not get to put my data and everyone else's at risk to catch a few bad guys.