[Suicide Junkie]

Actually as remote as it is likely to be placed, it would be fairly safe. It not like a hijacked airliner would be able to sneak up on it if the nearest flightpath is thousands of miles away. But on the other hand it wouldn't take a fully loaded airliner to bring it down.

Actually, if you plan ahead a little bit, it would take a lot more than that to bring it down.

If its out of the way, you have lots of time to take the plane down. They also have a very small, probably invisible from a distance, target to hit, so there is a fair chance they'll miss anyways.

Say a plane does come along and cut the ribbon. You will lose less than 30,000 feet of cable. Probably a LOT less, since they'd probably have to use the base station to locate the cable.
How do you repair the system? Just unwind some more cable from the counterweight station, and you're back in business...
Then put some more spare cable on the next elevator going up.