The exchange of fire between Hezbollah and Israel Defense Forces troops in the Har Dov region Wednesday, in which no one was injured, was viewed by the IDF Northern Command as the successful fruit of its two-year policy of containment.

This may seem a strange conclusion, in light of the fact that the initiative is in the hands of the opponent and that fear has returned to the residents of the northern communities. But systematic groundwork leading up to the attacks and restraint in the response have succeeded in restricting the clashes to exchanges of fire between armed forces, and excluding the civilian targets in the Galilee and further south that are within range of the Hezbollah rockets.

The most important outcome of the incident was the fact that the damage was light and was bearable to the extent that this forestalled the necessity of a major Israeli response. On the other hand, this state of affairs will only last until the next incident: Then, if a rocket causes casualties, the results would almost certainly lead to a chain reaction of strike and counter-strike.

Last Wednesday, just hours before he was due to depart for a visit to the U.S., IDF Chief of Staff Shaul Mofaz toured the northern border together with Northern Command chief Gaby Ashkenazy. The two knew that at any moment the self-restraint that Hezbollah has displayed since October 22 last year could come to an end.

In conversations with regional commanders, Mofaz warned against periods of uncertainty and a possible deterioration in the situation, from a localized attack initiated by Hezbollah under Iranian guidance, to a total conflagration including Syria.

The scenario of military escalation spreading like a forest fire from front to front - Lebanon, Syria, along the roads leading to emergency storerooms along Israel's home front, and even to Egypt - concerns the IDF and spurs the General Staff to carry out exercises testing the readiness of the commands and the divisions.

With the conflict in the territories continuing at a controlled level, the key to a regional escalation lies in the north, where commanders are working toward reducing points of friction and view escalation as a possibility, not as an inevitability.

The Northern Command views Hezbollah, which waited three months and a day since the last attack, as undergoing a test of its freedom of action, following serious American pressure on Syria, Lebanon and Iran.

The Northern Command and IDF intelligence are convinced that Hezbollah Secretary-General Hassan Nasrallah is listening to the growing calls in Lebanon to avoid an escalation which would further damage his country's struggling economy. At the same time, Hezbollah are involved in training Palestinians to carry out attacks in Israel.

Contrary to earlier reports, members of the Iranian "Revolutionary Guards" are continuing to aid Hezbollah. Iran is continuing its attempts to supply the Palestinians with arms and Hezbollah continues to call on the Palestinians to step up the intifada.

The recent focus that Israel has placed on Iran has ignored the usual prime suspect - Syria. However, on Wednesday, the IDF reiterated that the person with overall responsibility for Lebanon is Syrian President Basher Assad.

Ever since the IDF withdrawal from Lebanon in May 2000, many have speculated on the ramifications of the Lebanese experience and the conflict with the Palestinians. Fewer people have looked at the other side of the coin: that the Hezbollah leadership and Assad have been surprised by the intransigence of Israel in the conflict with the Palestinians. In the Northern Command, they believe the steadfastness of the Israeli public has acted as a deterrent to Syria and Hezbollah.

The wider context, of course, is American pressure on Syria to act against the terror organizations. Following recommendations by the head of the IDF Head of Plans and Policy Directorate, Major General Giora Eiland, the U.S. was convinced to pressure Syria to act against the headquarters of Hamas, Islamic Jihad and the Popular Front for the Liberation of Palestine, which are based in Damascus, and against Hezbollah in Lebanon.

Reports from the IDF of Al-Qaida fighters fleeing to Syria and Lebanon ensures that American pressure will continue even if the next phase of the war against terror takes place in Somalia or Yemen.

Senior U.S. military commanders held meetings with their IDF counterparts last week; in addition, a visiting group of U.S. Congressmen led by House of Representatives Democratic leader Richard Gephardt, met with Defense Minister Benjamin Ben-Eliezer following meetings in Syria and Lebanon.

These meetings left the Israelis with the impression that Congress, and the Bush administration, were increasingly worried by Iranian influence on the Lebanese border and the possibilities of escalation. The Americans have no intention of letting Hezbollah and its patrons draw the region into an all-out war that neither Israel nor the Arabs want.