They could have used grappling hooks and longbows.
The hunting down of global enemy number one came about through the type of detective work and on-the-ground stealth military activity that might have been considered ingenious, oh, among 15th-century ninja warriors or the ancient Sumerians. Ian Fleming would not have had a lot of raw material to work with here.
The real story on all of this will likely emerge in the next few hours or days, so everything written here may be moot from the time of posting. But it seems like what happened was that a bunch of intelligence types sat around a table and pieced out where exactly Osama bin Laden could be.
They decided that he couldn't be in a cave or in the Pakistani frontier territories because that's exactly where everybody thought he would be. So there were probably only two other places in the world he could be holed up: somewhere else in Pakistan or in Somalia. Afghanistan probably would have been okay, too, except there were just too many cops.
So, if, in the most likely case, he was still in Pakistan, he would probably be hiding ostentatiously in plain sight. And that's when old-fashioned shoe leather and detective work came into play. Why was an obviously non-affluent Pakistani man going to and from that complex with the insanely high walls just a few miles from the capital city of Islamabad?
The whole affair turned into a game of low-tech one-ups-manship. The compound itself reportedly had no phone or Internet service. The place was off-the-grid, even if it was only a few miles from military facilities.
It's true: At the point that intelligence agents began to trail Bin Laden's courier, drones and satellites probably were probably trained on the Abbottabad complex. But these were really just high-tech security cameras, and could have, if necessary, been replaced with Galileo-era-vintage spyglasses. The whole operation, from beginning to end, was a masterpiece of Humint, the type of human intelligence that the U.S. was criticized for lacking immediately after 9/11. (Let's not go overboard: The killing of two Pakistanis by a CIA contractor in January shows how things can still go terribly awry.)
Still, the U.S. capability has matured in the intervening years. Human smarts were even brought to bear in the decision to dispose of the body at sea in a traditional Muslim ritual. You can see the same intelligence types sitting around the table. Should we keep the body? If we don't, will anyone believe that it's him? And then, the immediate response: Screw the "birther" types; if we leave the impression that we're prying and poking at the body as it were an alien's, the "street" will explode. The past 10 years has been an intensive instruction course in cultures most Americans hardly knew existed, an immersion that is just now beginning to pay off.