About two weeks before the Six-Day War, Haim Bar-Lev was summoned from a sabbatical in America and appointed deputy chief of staff. This was at the height of the waiting period, when the army was pushing to start the war but the government was hesitating, thereby sowing consternation among the public. On the day he donned his uniform, Bar-Lev coined an unforgettable phrase: "We'll hit them hard, fast and elegantly." In essence, this was a pungent translation of David Ben-Gurion's military doctrine: that because we are a small country we must move the war to the enemy's territory whenever we are attacked and achieve a rapid victory. Unfortunately, it hasn't always worked that way.

When Ehud Olmert declared this week that "the patience, determination and endurance of people on the home front will determine our ability to complete the job," all my fuses blew. This man dragged us into the 33-day Second Lebanon War and turned the rear into the front. How does he have the nerve to preach to us and tell us what is needed for the war against Hamas to end in victory? What achievement did the Second Lebanon War bring us, other than exposing Israel's soft underbelly and eroding its deterrence?

The Israel Defense Forces' surprise aerial assault on Gaza on Saturday proves that amateur pianist Ehud Barak is a superb player in the military sphere. The secret preparations and deceptive messages, at a time when dozens of missiles a day were landing here, allowed Hamas' leaders to sleep undisturbed. In their enormous arrogance, they were caught unprepared and panicked.

The air force functioned, and is functioning, as it knows so well how to do - and unlike some of my colleagues, I will not conceal my enjoyment of the flames and smoke rising from Gaza that have poured from our television screens. The time has finally come for their bellies to quiver and for them to understand that there is a price for their bloody provocations against Israel.

This week, Barak quoted the French saying "war is war." But a difficult decision still awaits him: What next? For all the success of the aerial operation, it is not clear that bombings alone can shut down Hamas' growing ability to launch mortars at Israel's home front. The air force is generally only the appetizer - the first course. But tasty as it is, it is not enough.

Assuming that the movement of infantry toward Gaza is not mere psychological warfare, one option is to slice Gaza into several districts and leave smaller forces behind in some of them for a limited time in order to complete the tasks that the air force cannot accomplish. On the other hand, the IDF will become a focus of attacks if it enters and remains in Gaza, just as it was during the first Lebanon war. The overnight exit from Lebanon in May 2000, on Barak's orders, taught the terrorist organizations that a prolonged presence in hostile territory is the Jews' Achilles' heel.

Clearly there is no intention of occupying Gaza, just as there is no intention of making do with an aerial assault. Despite the call-up of the reserves and the concentration of tanks and artillery batteries near Gaza, it must be hoped that there is also no intention of sending large forces into Gaza, if at all, or of remaining there beyond the time needed to achieve defined goals, such as localized cleansing operations and holding the territory until an international force arrives under some arrangement or another.

Some defense officials say Israel must do everything in moderation. It must not send ground troops into Gaza other than for brief, pinpoint incursions followed by a rapid exit. The concentration of ground forces is not meant to destroy Hamas, but rather to set a price for future Qassam rocket launches. A prolonged stay or an expansion of the war would make this the sort of operation that the world will neither understand nor accept.

For now, Israel enjoys the support of the American administration. But as January 20 approaches, the date of Barack Obama's inauguration, Israel must be well "post-Gaza." Don't think that Obama will focus exclusively on the economic crisis as his first priority. A president can take a stance on several issues at once - and we don't know what his stance will be on this war and all its ramifications if we fail to end it at the right time.

There is no doubt that Barak is aware of all the possible complications. And no one understands better than he that while it is impossible to make Hamas disappear and it is impossible to completely destroy its missile-launching capabilities, it is possible to destroy its motivation to use them. Just as he knew when and how to begin the operation, we must hope that he will also know when to end it.