It's a covert operation - up until the point where you infiltrate the base. All you need to do is get in and blow up ... something. You don't need to be alive after that...
I haven't been able to make it *to* the base so far.
I get the air carrier, but it gets shot down by the SAM's. So I have to blow up the SAM sites, always take a good chunk of my health away because they blow before I can get away from them.
Plus there are some buggies driving around near one of the missile sites, and they kill me before I can get away or terminate them. :-?