"The primary threat to Gaddafi over time was internal, nukes would not have protected him. What was he going to do, nuke his own territory? The same was true for Assad."

Have you checked, how many outside interventions both countries had and still have?

Labelling this as "internal" is pretty missleading. If both dictators would have had nuclear weapons ready to launch, no foreign bomber would have dared going in against the regime.