Taliban already has a presence in Karachi, a big one that.
As far as operations in NWA is concerned, the government should announce it if they think it would solve our terrorism problem. The previous operations have only pushed Taliban deeper into Pakistan and across the borders in Afghanistan (Kunar/Niristan etc). Any operations in NWA will push the taliban into Khost, Paktia and Paktika. They already have a support structure there. Will that solve the problem? I dont think so.