The constitution awards birthright citizenship and so does the 1951 law and that has never been amended. Pakistan has accepted Afghans as refugees of war for the last 50 years , its why UNHCR has such a big presence in the country for last 50 years. Afghan and Bengali children already have gained citizenship via these laws
The constitution doesn't allow children of enemy aliens.
Pakistan has accepted a small part of the total afghan refugees (POR) with limitations. Limitations that they broke, like illegally buying properties using proxies, engaging in illegal trade using proxies, non UNHCR education etc. They were supposed to remain in camps and under UNHCR umbrella, they broke the deal long ago. Even the most liberal countries denaturalize citizens for engaging in crimes like these. Let alone non citizens.
there is no mass migration to West, it's a mirage created by white supremacists who in turn are merely a tool of oligarchy that wants to distract from it's getting richer and richer and shifting blame to women, poor and immigrants.
Come of it. Anyone can Google Demographics statistics for key western cities. Just take London. Looks like mandi bahauddin. 55% non white. Canada looks like Lucknow. Frankfort looks like Kabul.
The worse thing is that these immigrants don't even bother to integrate. They continue with their tribal hostilities abroad. Indians and Pakistanis fought street battles in Leicester couple of years ago. Afghans regularly fight with Pakistanis at stadiums, from UAE to UK. And regular knife each other in Germany.
A generation or two, they get into second and third tier political power and use that to engage in tribal geo politics back home. Net negative.
The fencing is among a tiny part of the border and has not stopped militants or smugglers or ordinary people. It's for show. The deportations etc are also for show as the border remains porous and people will easily come back later. Corrupt Pakistani system will also sell ID cards, documents whatever to Afghans just like it has for last 50 years.
Fencing was never to stop anyone. It was to slow them down enough for border forces to react to mass scale attacks. The entire destructions of multiple tashkeels near the border is thanks to that fence. Albiet it needs to be manned properly.
As for the rest, this is where "it is impossible" bunch try to undermine efforts and tell Pakistan to bend over and take it instead. Yes, some might return, but that's better than letting every afghan in and giving everyone already here citizenship.
Deportations is a longe term policy not a short term one. Keep deporting, wether millions are here or dozens are here. Eventually the numbers go down to a reasonable level.
As for ID cards, yes, Afghans in Nadra, especially in chaman, are a problem but not an unfixable one. Illegal Afghans with IDs don't have family trees in the database. One system heck will cough out most of them. Again, something "it's not possible" bunch would like us not to do in the first place. One might wonder regarding their true intentions.
Same corrupt system treats Pakistanis same way.
Divide and rule will not work here in this matter. Pakistanis overwhelming stand with the system against the illegal settlers form Afghanistan as far as mass deportations are concerned.
And last, if "it's not possible", why are they so worried?