Not to post reason in the midst of a nice offtopic debate, but let me respond to the OP with this.

I went to Cairo for the first time last year to pick up an AONE RTW ticket on BA/AA. Was a bit worried about safety and security myself, especially since I still look somewhat ex-military, which I am.

Let's put it this way. There are certain parts of Cairo - especially the suburbs - that I wouldn't feel comfortable walking around in, as it is very clear Westerners aren't welcome there. (I got together with a native college friend of mine who drove me around a bit and he mentioned the fact that it probably wouldn't be a good idea to hop out of his car in this particular location.) But then again, there are certain parts of DC or Chicago or Boston or New York that I wouldn't feel comfy walking around in either.

Parts of Aswan are supposed to be a hotbed for radicalism, so that's also a concern.

But the fact of the matter is that Egypt spends a whole lot of resources on making the country safer for tourists than for the common Egyptian, as the $20B or so per year it brings in is crucial to keeping the country afloat. (I vaguely recall that it went down about 40% once the Iraq war started and the Egyptians were not real happy). That means you'll see AK-47 toting "Tourist Police" (they wear the title it on their armband) at virtually every place you might consider visiting. That also means that as was said elsewhere almost every upscale hotel worth staying at (e.g. potential bombing target) has several metal detectors and private security staff. And it also means that any bus trip or cruise trip you might take will also have private security.

Sure, if you're wearing a super-bling-sized Star of David and decide to take a Quran out and desecrate it on Friday in front of a mosque waving an American flag and screaming "Death to Allah" you're likely to face Darwinian deselection. And if you haven't been to a third world country there are precautions that you should always take. You're not walking around Western Europe, and acting like a dumb American tourist will always get you noticed. But in general people are actually curious to hear a little bit about America and American politics that proves we might not be this monolithic cowboy-hat wearing country after all. 90% of Egyptians have an unfavorable opinion of the US but that doesn't mean they aren't curious to meet an American.

Also, if you're a male or a couple you should be fine. If you're a female, I wouldn't go alone unless I knew a bunch of Arabic or were in a group or had already made prearrangements to have a good tour guide, as Egyptians tend to look at single Western women like hookers. (You should have heard my university-educated tour guides.) Two women together is fine though.

And while, yes, its slightly possible you might get blown up by a car bomb, it is a lot more likely you will be fine, if just annoyed by the baksheesh (tipping) culture and the inevitable stop at the carpet, perfume, papyrus, and any other 'factory' where they will try to get your Western money in any number of sales pitches for schlock.

And edit: Since the OP sounds like they're Canadian, my apologies for lumping you with Americans.