Steve Jobs famously called the computer a “bicycle for the mind,” an extension of ourselves that would not only make life easier, but improve it. And although the idea began with the Macintosh, the device closest to this particular Jobs ideal didn’t arrive in earnest until the iPhone.

The iPhone is the computer for everyone, the one we can all use without an instruction manual and without extensive training. We use it in line at the DMV and as we wait for the water to boil; we use it at the breakfast table and (though it might be a bit crass) on the toilet. It is a part of us, it is us. We work and we play on it, ask it questions when we don’t know the answers, even send photos and communications we’d be embarrassed by were they ever let into the light of day.

I wouldn’t let you know what I say to my wife in the privacy of our bedroom, though if you had a warrant and a surveillance team, I suppose you could listen. But even more than that — more than that — I’d never let you read my mind, let you know what I don’t even choose to tell her.

Never.

Steve was right. This little computer is a bicycle for the mind, but not in that it lets me do things faster and more efficiently (it does that, too). It’s an extension of the mind, a part of it, an inextricably intertwined augmentation of our thoughts. The iPhone (and the smartphone in general) lets me store more thoughts, remember moments more often and more vividly, and it is able to do so because I trust it. I trust that my musings and photos and videos are safe there. And more and more as time goes on, this has become true. It’s not a fetishization, Mr. President, it’s a fact. The contents of my phone, and other devices where I store things that I have yet to elect to share with the world — and may, in fact, never share — are private.

These unshared thoughts, imaginings, creations are just that: unshared. They are private.

And no. Not you, not your three letter organizations, not anyone has a right to see them if I’ve decided that they are so. Take them by force if you can, legislate if you must (and you should), but don’t leverage the locksmith as if it’s his responsibility to let you in. He doesn’t have a right to it either.

This device is a digital extension of my mind, a container for my thoughts, a memory of more precise capacity and greater longevity, a secret part of who I am, that I may open to you if I so choose. There is a key, but like the one for my biological mind, I and only I am the single person who may use it.

No one — not even the President of the United States — has a right to that.

Would you read my mind if you had the chance? Is that where this ends? I thought that we had the right to remain silent, to withhold that which would incriminate us. Do we have that right? Or will it dissolve as soon as it becomes technically feasible to circumvent it?

The particular phone you want to access today may not have been an extension of its user’s mind. But the key that will unlock it would unlock mine and my wife’s and someday my children’s. It would open a door for actors from less benevolent governments, if only enough to slip in the steel toe of a combat boot. And as we know, once a crack has opened, any number of plague ridden vermin will find it. It is a matter of time, an outcome so certain that decades of research and billions of dollars have only just been able to stave it off.

And so, though I have the right to remain silent, I choose to say this: many have claimed that this case is not about one phone (the government seems to see it otherwise). I will contradict them, arguing that it is about precisely this one phone because one is all. By opening one, you’ve opened them all.

By weakening one, you weaken us all.