I dont understand this conflict.
The easiest way to explain this very complex issue to someone from Türkiye is for you to look at the TTP as an entity similar to the PKK, the TTP is the exact equivalent for Pakistan. It is an ideological, violent terrorist group responsible for thousands of Pakistani deaths.
Why doe Pakistan has a problem with Afghanistan?
Issue with safe heavens inside Afghanistan: Just as the PKK utilizes mountainous borders and weak state control in northern Iraq and Syria to launch attacks into Turkey, the TTP uses Afghan soil as a launchpad to attack Pakistan.
Issue with Afghan Taliban supporting TTP with arms, ammunitions, safe harbor and logistical support:


I always thougt the ISI had good relations with Taliban and even supported them in the past?
When the Afghan Taliban took power in Kabul in 2021, Pakistan expected them to rein in the TTP. Instead, the Afghan Taliban treats the TTP as ideological brothers, refusing to crack down on them.
This threat we face is similar to the one faced by Türkiye along its southern border with Syria. There are factions within the Taliban, not all Taliban factions are pro-Pakistan, the current Taliban regime doesn't recognize the international border of Pakistan with Afghanistan and has openly stated they want to claim all of Pakistan to create Greater Afghanistan:
Pakistan has hosted millions of Afghan refugees for over four decades. Sorting peaceful refugees from embedded TTP militants is an astronomical intelligence challenge, this is why you see threads about deportations of Afghans.
What changed? Did the Taliban choose the side of the Baluchis or
Pakistan initially backed Afghan factions decades ago to secure its western border. Today, that policy has resulted in severe "blowback," where the very forces Pakistan hoped would bring stability have enabled a terror group (the TTP) to wage war against the Pakistani state.
India has long sponsored terrorist activities inside Pakistan, their strategy relies on three things: Destabilize Pakistan, Dehumanize Pakistan, Damage Pakistan.
Recording of Indian Intelligence Major coordinating attacks with a terrorist in Pakistan.
Pakistan's current stance not
anti-Afghan, but as
strictly pro-security, identical to Turkey’s "zero tolerance" policy for cross-border terror.
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I hope this helps make some sense.