While watching news coverage of the fighting between Israel and Hezbollah, I saw some clips of incoming rockets descending on Israel. I briefly wondered why Israel wasn’t using Patriot missiles or otherwise trying to shoot down the rockets. Then I thought about it, and came to the conclusion that the Israelis knew what they were doing.
What a lot of people tend to forget is that anti-aircraft (and anti-missile) weapons aren’t death rays. An airplane or missile that gets shot down is just that — not destroyed, shot DOWN. It comes down to earth in various pieces of various sizes in various places. The old video game “Missile Command” never dealt with shrapnel.
And when that object is destroyed by a missile, then there’s even more explosives and debris raining down.
Anti-missile warfare is a very challenging science. You have to balance the potential harm of letting the incoming missile hitting its target or risk shooting it down — in essence, weighing the potential damage to where it’s headed against where it will land versus what will be below it when you attempt to destroy it. For example, a missile that looks like it will overshoot the city and land in the ocean should be left alone. On the other hand, one heading for an oil refinery after overflying a hunk of desert desperately needs to be stopped.
Complicating the calculus are a couple of nasty variables. The missile is moving — the area under it is constantly changing. It can cross vacant areas, farmlands, schools, hospitals, and crowded neighborhoods on its way to its final destination. And it’s moving fast — the decision to shoot or ignore must be made very quickly.
Also, sometimes the missiles miss. They are usually programmed to self-destruct after missing their target, but once again you have the problem of shrapnel and debris falling back to earth.
The defenders have a few advantages. They tend to be emplaced in familiar land, and often have time to map out the area, designating which places are safer than others to shoot down missiles over. Also, in Israel’s case, the missiles are almost entirely ballistic and unguided, meaning that once launched, their path is largely predictable, a matter of applied math. To the best of my knowledge, the only guided missiles fired by Hezbollah have been the anti-ship missiles that sank an Egyptian freighter and damaged an Israeli corvette.