Let's face it: Pak military is in no position to fight wars on behalf of Arabs and win it. Its simply impossible. However, what it can do is provide cheap manpower (foot soldiers) so that Arab citizens don't have to fight, and they can continue to live their lavish lifestyle by holidaying in Europe/USA, f*@k hookers and anything else you can think of. Anyone who's been to these Middle Eastern countries, or met their citizens abroad knows that they're in mood to sacrifice their lives (atleast not till the oil runs out). They won't even protect their own ruling elite lol - the security is delegated to foreigners. Americans have been milking these oil cows for decades now.
Pakistanis on the other hand are quite happy to fill this vacuum. One call, and millions are ready to sacrifice their lives for these Arabs - its no wonder our ruling elites are knocking on every door in ME ready to sign these 'defence pacts'.