This is the Pakistani counterpart of a similar program in Afghanistan. A danger is that these programs upset traditional power sharing arrangements for local problem solving. In most farming and shepherding societies, men with weapons are managed carefully and not ex officio members of decision-making councils. Access to weapons and ammunition changes village and district bases of authority forever, whether the guns support local religious authorities or secular power holders; the wise or the skilled, or the hereditary elite. The introduction and empowerment of weapons wielders always upset pre-existing power balances with the consequences that are serious and difficult to predict for everyone.
The Dutch colonial authorities in the Dutch East Indies, the French in Indochina and the British in Malaya learned after World War II that the local resistance forces they armed against the Japanese became the core of armed independent movements against the providers of arms. Pakistan already experienced this boomerang effect under earlier governments.
Creating local militias might help stabilize the tribes in Pakistan and Afghanistan. There might not be other good or quick options at this time, but proponents of the tactic should also prepare plans for the follow-on consequences. Disarmament is never effective; warlordism is almost unavoidable; arbitrary local decision-making backed by guns is common; armed insurrection against the warlords is a usual long term result.