Because if you can't do that, what's even left for terrorists to destroy?
Oh please. Imagine you have a guest at your house who asks to use the bathroom. You reply, "Yes, it's the second door on the left, and I haven't installed any recording devices in it." Would you seriously be surprised at your guest's sudden unease while relieving himself?
No one's saying that this is the OP's fault, but telling a flight attendant "I'm not a terrorist" is like saying, "Use my bathroom, I didn't install any cameras in it." Proffering information of that kind is just plain suspicious in itself.
There is a guest at my house, and I have a rule that nobody is allowed to take screwdrivers to the bathroom, because, as all my neighbours know, I am paranoid about people watching me as I take a crap (even though I have telescopes on the roof of my house pointing in all directions, and none of them into the sky; but that's a story for another day). So this guy walks towards the bathroom, and I see he has a screwdriver in his hand; I stop him, ask him to leave the screwdriver, which he does.
I make no further attempts to assure him I know he's not going to install a camera, or to be friendly or a human or something like that; I just bark my orders and waddle off. So after he finished his business, and because he's expecting to be over for a few hours and wants to clear the air, he walks up to me and says "About the screwdriver.. I didn't install a camera or anything, I just like to play drums on my knees while I poop. But I managed fine without it, so we're cool, right?"
I smily emptily, say, it's okay, waddle away... and then call the cops. Then I lie to them and say he took a screwdriver to the bathroom even after asked him not to, and onlookers actually turn my guest reacting to my pre-existing suspicion of them installing a camera in my bathroom into my guest raising that suspicion in the first place. The last part just boggles my mind.
That is not the same. He wants to fend off a personal stigma. Saying: "There isn't a bomb in my bag, if you must know. Here's my coat", that would be more in line with your analogy.
Oh please. Imagine you have a guest at your house who asks to use the bathroom. You reply, "Yes, it's the second door on the left, and I haven't installed any recording devices in it." Would you seriously be surprised at your guest's sudden unease while relieving himself?
No one's saying that this is the OP's fault, but telling a flight attendant "I'm not a terrorist" is like saying, "Use my bathroom, I didn't install any cameras in it." Proffering information of that kind is just plain suspicious in itself.