- Turkey is not in good terms with Israel.
- Turkey has militancy and is persistently unstable in terms of terrorist attacks.
- Turkey has dictatorial regime.
- Turkey is negotiating with Russia or China for purchasing missile defense which could undermine NATO's security.
- Recently, Turkey has alienated the USA in the incidents like Coup d'etat and Syrian crisis.
- .... ... ...
On the other hand,
- USA doesn't sell arms to Pakistan or arms sales is continuously vetted.
- Lots of sanctions went through Pakistan latest of which is to sanction seven entities related to missile development.
- Almost all Western countries stopped arms sales to Pakistan.
- ... ... ...
What makes Turkey to continue as a major Western ally without much trouble while Pakistan is not?