And it's not unreasonable for people to ponder such things when they look at history, see the parallels to today, and realize that they _could_ be targets. For example, I'd imagine that there are quite a few Muslims in US pondering these very questions right now.
It's the specific lines that some people state ("registration of all firearms", seriously?) that expose questionable judgment on their part. Or, alternatively, the lines can be reasonable, but their perception of reality is so skewed that they treat absolutely mundane things as crossing those lines in their mind. All the conspiracy theories around Jade Helm were a good example of that.