Perhaps pakistan can learn something from America's involvement in Mexico.
America has traditionally backed upstart cartels against powerful cartels. Then when the powerful cartel is vanquished, america will back a new upstart cartels against their old cartel keeping Mexico in perpetual violence and no dominant super cartel.
Pakistan, using military intelligence and some saudi money can infiltrate and support weaker warlords against Taliban and when that warlord becomes too powerful, just ditch them and support another upstart warlords.
I know its not going to benefit the Afghan people but they should be the acting responsibly and if they can't, then others are free to mess with them.