fedya,
You are treading on classified territory regarding the operatiomnal charactistics of individual weapon systems. You can look up basic unclassified information on the physics of fire control ballistics. The variables to consider are the distance speed altitude and target angle of what you want to intercept as well as the speed flight time and sensors of the weapon. Target angle means is it coming at you or going away or crossing past you. The more complicated the problem the smaler the area around you in which your weapon can achieve an interception. I will now make numbers up and pull them out of my ass. Consider this problem, you have just purchased the latest Raytheon Super Duper Ultra missile system. In theory it can fly over 200 miles to engage a target. If you are sitting in the ocean and get a report that a nice big slow Russian Bear bomber is taking off from a runway almost 150 miles away. You can probably fire a missile and pick that plan off as it is going down the runway. The US Navy did something like that to a Mig in Vietnam. Now consider that the same ship with the same weapon gets a report that someone 20 miles to your North-west is shooting a small fast missile at a city 30 miles to your North-east. Would you be able to intercept that target? It would have to be a heck of a good weapon to pull that off. The best way to target an enemy’s weapon is to destroy the launch site. The second best way is to shoot from where the enemy is aiming at and intercept the incoming weapon coming straight at you as far from you as possible. The farther you are from his target the less time you have to intercept him.