Because, if you’re one of those Americans unlucky enough to have left your security clearance in your other pair of pants, questions about either receive essentially the same answer:
“You’re not cleared for that information.”
An informed citizenry is the basis for democracy, say the civics books. But whether the subject is the coming punitive attack on Syria, or the latest developments in the drug war, an informed citizenry is less popular than a 4 am car alarm with Administration officials. It's less welcome than French kissing at a family picnic.