Daoud khan president of afghanistan was a rabid nationalist of Afghanistan pushing for pashtun nationalism. He engaged zulfiqar bhutto's pakistan in a proxy war causing dissent and sabotage in the border land. Daud khan saw Durand line as a false border (afghanistan doesn't actually recognise pakistan border) so believes Pashtunistan, and balochistan are rightful afghan land. So what would happen in 1975 if Daud khan invades pakistan? I believe pakistan would win due to better military and try and seize the wakhan corridor.