I'm not interested in what politicians say either, except to the extent that in a court challenge, when judges look to interpret the intent behind the statute, they have a clear signal by the authors of the bill that the statute was designed to prevent the collection of personal information by ISPs. Which was why I brought that up.

Your second graf begs my question. Obviously we're both aware of the ECPA and SCA. My question was, in what way do the preemptions on those acts materially harm the public interest? Put it this way: if you think that CISPA is in direct conflict with SCA, then clearly you can imagine situations in which e.g. Facebook could collect Netflow data from a DDOS attack and then worry that they'd somehow contravene SCA by sharing the information. Doesn't that "conflict" explain the need for an act like CISPA?

I'd also note that the first three acts you cited --- obviously the three most important, because they cover the integrity of online communications in general and not with respect to any particular application domain --- already contain exemptions similar in spirit to the ones in CISPA:

* ECPA permits providers to collect and in some limited cases share information that is related to the maintenance of their own infastructure

* SCA permits collection and monitoring of stored communication by the operators of stored communication services

* The Wiretap Act allows operators to intercept and monitor signals causing disruption to networks

CISPA harmonizes collection and sharing of data in cases of direct adversarial attacks. Compared to the exceptions in (for instance) ECPA, CISPA is narrowly tailored and very specific.

Furthermore, when you point out all the laws encumbering sharing of attack information, you start to make the preemption point for me. It may already be possible to share attack information, so long as it doesn't involve raw emails, and the attack information is shared by telecom providers under the ECPA maintenance exemption. UNLESS YOU'RE AN AUTO INSURANCE COMPANY, in which case Congress helpfully (and reasonably!) enacted a specific privacy regime under DPPA, which means now simply to have Progressive push netflow records to Verizon they might have to incur $50,000 in legal review which by the time it's done the attack will be over.

Instead of repeating my original question --- how exactly does CISPA conflict with existing privacy laws in ways that harm the public interest? --- why don't I ask the question in a different framing. If we stipulate that the problem we're talking about here does exist --- that Advocate Health Care in Illinois would incur significant and unnecessary legal risk in pushing netflow DDOS information to a public clearinghouse --- what is the privacy-protecting language YOU would like to see in a bill that aimed to address that problem?

Incidentally: can you do better than thanking me for a polite response? I'm not actually sure I'm being that polite anyways; I feel like I'm being blunt and direct. But on the other hand, you wrote a comment with a complicated technical question last night at 1:00AM, and when you didn't get a prompt response, you accused me of "handwaving". Can I argue now that it it's pretty obvious that neither you nor I is "handwaving", and that we've both done our homework, or at least way more homework than most CISPA commenters have done? Instead of thanking me for polite responses, could you instead just not impugn my motives or intellectual honesty again? We can then just chalk our initial static up to "message boards and politics".

PS: The worst, most crazymaking thing about CISPA debates online is that they invariably put me in the position of "CISPA advocate". I have a position in the CISPA debate: "CISPA is not evil". I think if you believe like I do that CISPA is facially benign, the way organizations like EFF are choosing to message against it starts to get disquieting. But my position does not carry into "CISPA is a great idea". A sane argument against CISPA is that it forestalls a needed reform across all online privacy bills to enable network security to function sanely. CISPA might be a bad idea. I am not a CISPA advocate. I just don't think it's overtly contrary to the public interest.