Sea Harrier FA2 - a modern-day F6D Missileer?

Below is quote from a Royal Navy Sea Harrier FA2 pilot in an article in
the International Air Power Review vol. 16.

"Our tactics are based around the capabilities of our jet. For
instance, we do not like to go into the visual arena. We much prefer
engaging our targets from long range and that is why our main
configuration comprises four AMRAAMs. For target designation, we use
our left thumb to move a target-marker on the radar screen. When faced
with multiple enemies, we can ripple-fire our AMRAAMs in quick
succession."

From a mission point of view, it looks like the Sea Harrier FA2 could
be considered as a modern-day single-seat F6D Missileer in effect. Of
course Sea Harrier FA2 could bomb as well, although no better than the
Harrier GR7.

The original Sea Harrier FRS1 was conceived in the early 1970's as a
mean to drive off / shoot down the Russian long-range maritime
reconnaissance aircraft. When the FRS2 (FA2 after 1994) was projected
after 1983, what was the main threat - Backfires? MiG fighters? or
still the same Bears? - it was supposed to counter?