That's a fair assessment. It was meant to reflect my honest SWAG at where UBL might be found - Afghanistan/Pakistan/Turkmenistan/Uzbekistan/Tajikistan.
I want to address your tagline while I'm at it, since it seems to me a valid, if poorly considered question.
I have often proven a negative, and most professionals that have dealt with sensitive, proprietary, confidential or classified materials have.
But that's probably not a good analogy for the chattering class, so let's try one more base:
Ever been caught chewing gum where you're not supposed too? Back in a younger day, perhaps? Let me see if I can set the scene....
Auth: "Iconoclast, are you chewing gum?"
Iconoclast: [gulp] "No."
(A negative which must now be proven)
Auth: "Open your mouth." [Visually inspects] "Lift your tongue."
Iconoclast: [Complies]
Auth: "Iconoclast, what did you do with the gum?"
Iconoclast: [Shrugs]
Auth: "Did you throw it away?"
Iconoclast: "No."
Auth: "Did you stick it under your desk?"
Iconoclast: "No."
Auth: "Did you swallow it?"
Iconoclast: [Nods head]
(Proven.)
UN/US: "Iraq, do you have WMD?"
Iraq: "No."
(See where I'm going with this?)