You make a valid point about asking why we have got the stage where we want to be seperate from rest of India. And it does require some deep introspection by the Indian establishment. You state that we will/should not behave like our current Delhi masters. I have not seen one iota of evidence that we can even manage that.
Just extrapolate the behaviour of our current sikh leader - the SGPC, politiocians, Jathedars ,businessmen, academics , the 'movers and shakers' of the sikh world etc and see whether those types of people can be statesmen? My prediction is rather negative.
The only person I see who demonstrates anything like statesman like behaviour is sat in Patiala waiting for the noose.
But this still remains an academic point.
The reality is that as soon as Khalistan is gained there will be other groups who will want to further sub-divide the state. Whether it involves their greed, malevolence against the new created sikh state or hindu/muslim minority rights or whatever reasons. Furthermore, whoever these guys are, you dont need the brains of an Akal Takat Jathedar to know that indian intelligence commmunity will be in the thick of it.
You may call it a 'stupid' question but it still needs answering. We wont have the benefit of US backing that Israel has.
Also are sikhs willing to make the sacrifice required? Just look at any other new-born country: the process entails mass slaughter, rapes, pillage, anarchy, looting, ethnic cleansing, retribution murders. And that is AFTER independence. That is reaaly a question for those living in Pb to answer.