An attacker could certainly pay someone to break into your house from another country in much the same way as they pay their ISP to deliver malicious packets to your computer.

> Moreover, my computer is also a physical thing in my house, so it cannot easily be more secure than the house itself.

That isn't strictly true. If your device has full disk encryption using a strong password, physical access doesn't get you much in the way of accessing the data.

It's easy to confuse this with the explanation of why DRM can't work, but they aren't the same thing. To access data you need either the plaintext, or the ciphertext and the key. DRM fails because you need one or the other in order to watch the content, which means an attacker inherently has in his possession what is necessary to get the data. But a locked or turned off device with disk encryption only gives the attacker the ciphertext without the key, which is an entirely different situation.

> The patching of possible security breaches has become a weekly ritual.

That's kind of my point. Nobody recalls your car windows when they're discovered to be vulnerable to the "blunt force with heavy object" attack.

> And there are hundreds of thousands of unpatched compromised computers sloshing around in botnets.

Hundreds of thousands out of billions is what, 0.01%?