TTP is ethnic organisation with support from Many Pushtoon tribes on ethnic grounds.
Before Operation Zarb e Azb.
The entire Sipaah tribe gave their lands to TTP for training militants.
Leaders of Sipah clan in Khyber say govt has asked for large sums before they are allowed back to their villages.
www.dawn.com
The entire North Waziristan was manufacturing suicide vests, IED and other explosives for TTP.
After Zarb e Azb , the most amount of terrorists were released by Peshawar High Court, and often the judge surname was "Afridi " or something other Tribal surname.
Until this ethnic comradeship stops, the TTP will keep coming back.