Osama Bin Laden's Drink

Okay, listen up, you smooth-brained mammal. You asked for this explanation so here it goes. You probably think that Manhattan is some city. But that's not what makes this funny. The joke plays on the name of the cocktail "Manhattan". Osama bin Laden is known for attacking the World Trade Center on 9/11. The World Trade Center is in Manhattan, New York. So, instead of asking for a regular Manhattan drink, you're asking for a "double Manhattan", in reference to the Twin Towers. Get it now, you potato?