In modern warfare we have ghanta airdefence ability. Last feb spice 2000 were released beyond our borders and they had glided 60km in our territory. They missed their targets is irrelevant. That day indians weren't lucky but that's not how it would always be. SAMs with 40km max range is no deterrence at all.. the are the SAMs if u can detect them you can always avoid them... longer range SAMs (120km above) are lethal because they have too much rocket power to track and chase. It gets more n more difficult to evade them. S400 though heavier system but due to its extra ordinary long range it would be very difficult for a strike group to avoid them. Either we get them long range systems or we should lower our expectations in high intensity conflict. We will definitely attain more damage than we can afflict.