I think that Reagan would have acted just as George W Bush did after the worst attack in American history.
In 2001 Reagan would not have had to devote so much of his massive military buildup and manpower to the European theater.
Only someone as ill-informed and manipulated as W. was by the Neocons could have come up with something as stupid as attacking a country composed of three sworn enemies only kept at bay by a vicious despot.
Attacking Zambia would have made more sense. At least we could have been in and out a lot quicker.