This means, if you are served a national security letter with a gag order saying to turn over my data without telling me, can you?
If you are not NSL proof, are you able to demonstrate who from your firm can, and cannot, by technical guarantee not by policy in the “signed agreement” sense, see my data, and can I see in an audit log any time and every time any of those people do see my data?
On the contrary, that scenario (as well as, "what if your SaaS provider or CSP is hostile?"), are great "clarifying" questions to understand the security architecture of a product that is very likely to see some incredibly sensitive data.
It is possible for the answer to be that a service is NSL proof -- with asterisks, and the asterisks are very interesting to discuss.
And no, it's not about the US security apparatus for most firms, although if you take a look at AWS's security teams, you'll see there is a lot of experience exchanged, and AWS does secure the US security apparatus' data.
Are you able to be “NSL-proof”?
This means, if you are served a national security letter with a gag order saying to turn over my data without telling me, can you?
If you are not NSL proof, are you able to demonstrate who from your firm can, and cannot, by technical guarantee not by policy in the “signed agreement” sense, see my data, and can I see in an audit log any time and every time any of those people do see my data?