Exactly.When W volounteered for Nam the 102's were being phased out.There wasn't enough time left in W's enlistment to transition to the 105(I think it was the 105,have I got that right?)
"(I think it was the 105,have I got that right?)"
F105's and F106's where already in service during that period of time. The F106 replaced the F102 rule as an intercept plateform. The F105 thud as you remember was not an intercepter but a fighter bomber by design.
So technically the answer would be that the F102 was simply at the end of it's service life as a front line intercepter. And as you are well aware the few F100's that where used in NAM where not used as the main Airforce fighter, nor where the F5's for that matter. The rule went to the F4 Phantom for the Airforce and the F8 Crusaders and F4 Phantomm for the Navy and Marines, with the F105 for the Airforce being the primary fighter bomber, and for the Navy both the F4 Phantom and Douglas A4 Skyhawk playing the rule of fighter bombers. And of course the Airforce using a few old F-101 Vodoos for recon flights of various sorts.
In any case GWB was simply not in the loop for active duty unless he would have somehow gotten into the Airforce and retrained in most probably an F4 Phantom.
That perhaps is a bit more verbose then what you asked for conformation, but that is my take on it.