As any 4-year-old knows, it's not polite to point. And as anyone who has ever taken a remedial public speaking class has been taught, pointing at your audience can seem aggressive or abrasive. The public speaking pros at Toastmasters don't recommend the wag, and they warn it is "considered impolite in most Middle Eastern and some Asian cultures." President Obama probably deserves credit for not adopting the odd, slightly castrated "Clinton thumb" as every other politician seemed to do in recent decades. Still, as you'll see in this very modest selection of photos, maybe it's time to put that gun in its holster for a while.