I think it's at least conceptually possible to pre-load a machine with software that doesn't pass any plaintext between you and it, and which the software image can't be modified without you knowing it.

I don't know about obscuring the fact of the connection between you and it though. Tor isn't enough by itself.

> which the software image can't be modified without you knowing it.

Nah. If you're worried about the kind of attacks that necessitate sending your own hardware, then, regardless of who owns title to the device, the firmware being replaced to snoop on or alter what is actually in RAM is in-bounds.

There are lots of ways of hiding persistence on a system, and decades of research along these lines. Once it leaves your possession, there's not much you can do to ensure that it still has unmodified code on it (assuming standard PC hardware).

Really though this isn't the threat model at all for someone who just wants to use a VPN, I only went there because the comment senselessly advised shipping your own hardware to the colo. That's the same privacy as using the colo-owned machine, which, for a VPN, is the same privacy as using a generic $5/mo VPN service, as in all cases the upstream can be trivially monitored (even in the case where it's your own, tamper-evident HSM-whatever remote attestation hardware).

Then why can't the entire FBI break in to an ordinary iphone, except by virtue of finding errors in implementation rather than the fundamental invalidity of the concept of secure hardware?

Why don't they just desolder the cpu and wire up an emulator and laugh at all those secure enclaves and encryption?

That whole thing was farce; the FBI got the unencrypted backup data from Apple. iCloud Backup is on by default for every iPhone, and is effectively unencrypted, and sends pretty much the entirety of the device's data to Apple every night when plugged in (using Apple keys).

Apple can decrypt the whole thing without any input from the user: they don't need their phone, they don't need their password, they don't need their keys.

The whole thing was a carefully orchestrated media dance designed to make it seem like the feds can't get the data off of iPhones. Not only do they have access to almost all of the data on almost every iPhone, they have access to it without a warrant or probable cause thanks to the FISA Amendments Act. Apple compromised over 30,000 accounts for the US government without a warrant in 2019, per Apple's own transparency report.