I'll give you two answers, one specific and one general. The specific answer: your post above already contained a good reply. The trouble was that it also broke the site guidelines. One can turn it into a good comment by editing those bits out. If I do that, this is what I get:
There's a difference between the government trying to take it by spying, and the government forcing you to give it away by contract as a condition of doing business. One you can take countermeasures against; one you can't.
That cuts not only the first two paragraphs, but also the flamey bits from the third ("Apparently you can't see" and "Hint:"). Doing all that yields a substantive, respectful reply. (I'm not considering whether it's a good argument here—just whether it's offside or not.) And of course it's fine to ask politely for the other person's source, or how they know what they claim.
The general answer: one good way to reply to a comment of the form "If you are in favor of A, then you must also favor X" is to mention significant difference(s) between A and X that show why A doesn't imply X. For example, something favorable in A that X lacks; or something unfavorable in X that A lacks. And to show why the difference is strong enough to break the assumed arrow from A to X.
There's an aspect to this that is unfair. pinkfoot's comment was pretty lazy (opting for snark and a drive-by rather than giving the reader enough information to really establish anything). If you're going to reply to a comment like that, the temptation is also to take the path of least resistance—for example, to vent, rather than to put much thought or work into a reply. The other person didn't put much thought or work into theirs, so why should you?
The answer is that you don't owe it to the other person, but to the general reader and the community. Your reply to such a comment will either raise the quality of the site or lower it. (Responding on the same level is lowering.) The two good options are: put in the thought and work to come up with a specific reply—cutting any flamey bits because by then you don't need them and they weaken your case anyhow—or, if you don't have the time and energy to do so, simply not to post.