Perhaps no Teen-series fighters in their current (in the case of the F-14 past) form. The air war over Vietnam was a rude awakening for the US Air Force and Navy.
Dog-fighting was back on the table even though F-4's could in theory destroy a target at 20 miles with a Sparrow - hence the lack of a gun on USAF C and D models and all USN ones. Yet technologically obsolete MiG-17's and 19's sometimes successfully harassed their more advanced US adversaries.
This led in part to US Navy Top Gun and USAF Aggressor dissimilar air combat training. Not to mention US and Western fighter design philosophy turning away from sheer speed (YF-12, F-108) to more agility (F-15, F-16).
Without Vietnam I guess we'd see perhaps see further developments of types such as the F-106 rather than the F-15.
Stealth may also have been a development which comes along at a much later date with no USAF and USN types being blown out of the sky by SA-2's.
Dog-fighting was back on the table even though F-4's could in theory destroy a target at 20 miles with a Sparrow - hence the lack of a gun on USAF C and D models and all USN ones. Yet technologically obsolete MiG-17's and 19's sometimes successfully harassed their more advanced US adversaries.
This led in part to US Navy Top Gun and USAF Aggressor dissimilar air combat training. Not to mention US and Western fighter design philosophy turning away from sheer speed (YF-12, F-108) to more agility (F-15, F-16).
Without Vietnam I guess we'd see perhaps see further developments of types such as the F-106 rather than the F-15.
Stealth may also have been a development which comes along at a much later date with no USAF and USN types being blown out of the sky by SA-2's.