When we were fighting them we had some successes, but than we backed down due to domestic pressure and terror attacks. Lal masjid is no longer a major den of terrorism, Mehsud too suffered some losses before the army backed down
The bottom line is that the mindless jihad of Taliban is not a proper foreign policy for Pakistan and nearly every country and the UN will pressure or threaten Pakistan soon if we don’t fight it. 100% success or even any success is not assured, but sitting back and doing nothing is just a recipe for being bombed by NATO/US.
We are going against UN resolutions if we let the cross border attacks continue into Afghanistan.