I don't know for sure, but its possible that a windows machine, if it did accidentally leak any meta-data about itself would be less unique than a linux install. Just a guess though.
If you assume your connected machine is going to get p0wnd, and you rely on the air gap to prevent your secure machine from being penetrated, you could run any OS you like, no matter your opinion of how much the vendor cooperates with the NSA.
Given that he's going to the level of preferring a store-bought USB stick over one found in a parking lot, it shows he's concerned about transferring malware. Not using the OS for which the most malware exists seems like a sensible choice.
After all, if you're going to all this trouble and inconveniencing yourself in the name of security, what's a touch more inconvenience with using an operating system that you're less user-friendly with?
Who is your threat? Are you worried about a spray-and-pray attacker who just dumps a bunch of malware out there? Or are you worried about being specifically targeted by someone who wants your stuff?
In the first case, a USB key bought at a big box store might be full of malware. In the second case, the big box store is the perfect place to buy something, as long as it's not the store where you always buy stuff, because the APT wants to keep his profile small.
That's a good point. But at the level this game is being played, I'm not sure if there is a difference. Schneier has made himself a high value target, so in the FOXACID hierarchy of exploits, he is worth risking the use of an expensively bought or developed zero-day exploit.
I don't think this is right. You should reduce the entire attack surface. Since Bruce is worried about malware getting in via a removable device and cites examples that attacked Windows he should not use Windows.
If you assume the OS is coming from a compromised vendor, what's to stop it from making wireless network connections on the sly? Or adding a 'phone home' payload to any outgoing data copied to removable media?
You could physically destroy the wireless capability. But not using or destroying the media inputs would leave you with a fancy typewriter.
Indeed. If he picked Linux or a Mac he'd have the advantage of being able to read most MS proprietary formats without the disadvantage of embedded code executing.
Seems to me the only reason to choose Windows for this would be to use Microsoft Office to read the NSA documents and he's stated that he's using OpenOffice, so...