The Sparkvark was indeed retired for political reasons.
Clinton hated the military (draftdodger that he was) and wanted to kill it off as much as possible.
In the ensuing battles, the Navy (with less expensive procurement and development programs underway) found money to keep the EA
-6B around where the Air Farce elected to remove vital aircraft for the ground attack and combat support roles in order to maintain the funding for the threatened but high PR
potential flashy F-22 program.
Had they chosen to keep the EF
-111 in service (and possibly the F-111G which was another victim and a far more capable penetration strike aircraft compared with the F-15E which however can perform the flashy AA
role) the funding would have been insufficient to keep the F-22 program on track which would have set back the air defence plans for the USAF
by at least a decade and possibly longer.
The idea to have the Navy provide the ECM role for the USAF
was a hoax thought up by the Pentagon and the White House in order to apeace congress to the decision to remove a vital platform from the USAF
Operational planners knew full well that the Prowler can never perform the role of the Sparkvark.
Where the Prowler is designed for barrier jamming (much like the lumbering EC
-135) the EF
-111 was designed to escort the strike aircraft deep into enemy territory flying with them at any speed and altitude. The EA
-6B cannot possibly hope to keep up with F-15s and F-16s flying hundreds of miles inland at low altitude and near supersonic speeds, a mission the EF
-111 could have performed without any problem whatsoever.
At the same time, the EF
-111 could never have performed the EA
-6Bs intended mission of screening an entire carrier battle group from attack by longrange bombers and escorting a squadron of slow A-6Es to coastal targets and loitering at altitude nearby while the bombers make dash attacks over that target.