When Pakistanis do the same, they are regarded as heroes. How many Pakistanis went to afghanistan to fight with the taliban in the Soviet-afghan war? Those mujahideens were hero worshipped by your society. Even your SSG was sent there. How many Pakistanis are fighting in wars in the middle east, on both sides? Now when Europeans or Americans do that, suddenly it's a bad thing? Something that Pakistan has always followed as state and non-state policy for decades? How many Iranians and hezbollah cadres fight in Syria? How come you are fixated on the handful of europeans? If it's done by muslim countries its all halal?
About these Uzbek fighters. Over the years, Pakistan has acctively encouraged hordes of Uzbeks to do their proxy wars. Indian army has killed quite a few Uzbeks and afghans, funnelled there by the ISI. These 'non state actors' were part of your state policy. Now that their aims in Kashmir have been frustrated, and their entry into India rendered impossible, and they have started jihading your own country, suddenly you wake up to their evils? This is called blowback. If you raise snakes at home to attack your neighbour, soon the snakes will bite you. Pakistan not only turned a blind eye, but actively encouraged Uzbek and Afghan militants to settle in its NW areas, as "strategic assets". You did not have the foresight to predict that they will end up hurting you more than India.
Anyway, fighting in wars is one thing. But terror attacks against civilians is quite another.
