Re: A little concerned about the future ...
Why should children who are third generation born in another country be passionate about a country that they don't belong to, and why on earth would you expect them to fight for that country (particularly when its inhabitants can't be bothered to do so)? I find this mindset odd, to say the least. I may be third generation French on one side of my family, but it doesn't define me, nor should it. I am interested in the culture, love the food, and have enjoyed vacations there, but I am an American by birth, and no amount of preoccupation with the country of my grandmother's birth will make me French. The same will be true for your children, whether you like it or not. Pakistan will be a place that holds interest for them, because it is their heritage, but it will never be their "homeland". In fact, most Pakistanis won't consider them to b Pakistani.
Concerns about a child's welfare are justified, but I think that it is easier to raise a good muslim child here, provided the parents do a adequate job. There is less confusion about Islam, and stronger ties in most muslim communities here.
Sometimes it's neccesary to identify with the countries of our origin, it gives us a sense of belonging, somewhere we truly belong and are accepted, something to fall back on.
In an ideal world it would be lovely if we didn't have to carry extra baggage with us, if we could just identify with the countries of our birth, but that's not always possible, we don't live in an ideal world. We're pack animals, we need belonging and when the "natives" tell us to "go back home you Paki bstrds!" it doesn't make us feel at home, even though we're born here and grew up here we feel like strangers.
It's different for you White people even if you have roots outside America/Britain, nobody sees/knows you as "Ethnics" so you can be of Polish, Irish, French etc. descent but you'll be accepted and blend in whereas with us Brown people it's not always as easy, and even harder now with our Islamic religion.
A third generation German in this country will be accepted by everyone even if his grandad was a Nazi and fought against Britain yet I'll never be truly accepted even if my grandad lost a limb or two fighting for Britian and serving the crown because I'm brown and a "Mozlem".