...First of all, Israel is responding not just to those recent killings but to a long string of attacks since it withdrew from Lebanon in 2000. The kidnapping was just the straw that broke the camel's back.

Second, as the Israeli government rightly points out, no country operates on the principle of responding to aggression with no more force than was originally used against it. During World War II, Germany sunk a lot of American ships and declared war on us, and in return we flattened its cities, killed or captured hundreds of thousands of its solders and occupied its land. That was hardly a proportionate response.

Now, it is true that Israel's counteroffensive has taken the lives of several hundred Lebanese civilians (many entirely innocent, others who sheltered Hezbollah rockets) and displaced perhaps half a million more. Every innocent death is a tragedy.

But the brutal fact is that civilian deaths are Hezbollah's strongest weapon. As Sheik Hassan Nasrallah, the leader of Hezbollah, once said: "We have discovered how to hit the Jews where they are the most vulnerable. The Jews love life, so that is what we shall take away from them. We are going to win because they love life and we love death."

Thus, Hezbollah places its rockets and other potential targets in homes, knowing that Israel cannot hit back without creating collateral damage. This does not relieve Israel of the burden of minimizing civilian casualties as best it can. The point is that if Israel has to operate under a code of ethics that renders civilian deaths unacceptable, then it automatically loses. The ramifications would be dire and ultimately aid the cause of Islamic radicals in such a way as to bring about many more innocent deaths over the long run.

The real question, then, is not whether Israel's counteroffensive is disproportionate but whether it's working...