[bigiain]

From a "non US person" perspective, I go to BitTorrent's website and read:

  Company Overview
  
  BitTorrent Inc. is an Internet technology company based in San Francisco. 

And immediately I've got _two_ things to worry about - 1) "will BT be evil/incompetent?", and 2) "will BT be leaned on by the NSA and be coerced into being evil?"

If you're a US company (or individual, or a company with US based management, developers, investors, or infrastructure) who are promoting security-related products in the post-Snowden era – many of us outside the US now have very good reasons to apply extra scrutiny to those products. Opening your source will make a _big_ difference in how readily suspicions of evilness can be allayed. As saurik points out upthread, having the source available doesn't guarantee the rest of the open source community will find and fix any carefully-enough-crafted backdoors, but keeping the source closed sends a strong message…

[Avshalom]

From a US perspective: The NSA doesn't lean on non-US companies because it is fully authorized to just hack them directly. Your data kept in foreign countries don't even have the nominal legal protection that US data does.

Unless you've got unbreakable security the NSA is well funded enough that it's irrelevant where you do business.

[morkbot]

Except that in the case of non-US companies NSA has to do the actual hacking. In case of US ones they simply need to "ask" a company to, say, handle them their master keys - much easier.