Jerusalem (CNSNews.com) - One day after Israel completed its historic withdrawal from southern Lebanon, the dawn of a new reality - there is no longer any buffer zone between Israel and its northern enemies -- is beginning to sink in.
Alongside the border fence, Hizballah fighters and south Lebanese civilians celebrated for a second day on Thursday, brandishing weapons, waving Hizballah flags and chanting slogans.
Israeli Prime Minister Ehud Barak told his cabinet and reporters that any cross-border attack would be treated as an "act of war" against the Jewish state.
"We hold the Lebanese government and the Syrian government responsible for any violation of these quite obvious rules of the game of sovereignty," Barak told a televised press conference officially announcing Israel's pullout.
"Once we are deployed along the border there is no legitimization, no justification, not even an excuse to shoot or to hit targets inside Israel," he said.
He repeated his "recommendation" that no-one attempt to test Israel's resolve in this regard.
"If someone is attacking Israel over its border and shooting, it is an act of war," Barak warned. "No sovereign government will allow salvos of Katyushas landing in [its] civilian cities."
At the border on Wednesday, Hizballah gunmen hoisted their yellow flags bearing the image of a fighter holding a rifle rising out of the word "Allah" on buildings abandoned by Israel and its collapsed ally, the South Lebanese Army.
One group of about 100 demonstrating fighters shouted across the fence: "We're going to kill you," according to reports from the area.
Members of the Israeli "Four Mothers" group, which spearheaded a public campaign for an Israeli evacuation, tried to speak to the Hizballah men through the fence, but their gesture was ignored amid the celebration.
The U.S. called on the Lebanese government to take control of the situation at the border and State Department said U.N. peacekeepers would "assist the government of Lebanon in assuring its effective control over the area."
U.N. envoy Terje Larson was due to meet with officials in Beirut on Thursday to discuss how U.N. peacekeepers could work with the Lebanese Army to fill the vacuum left by Israel's withdrawal.
But Defense Secretary William Cohen was not optimistic about the likelihood of quiet along the border.
"There's likely to be retribution sought against those who were, in fact, supporting Israel," Cohen said in Washington. "Much of the equipment perhaps will be used against the Israelis with Katyusha rockets being fired into northern Israel, which will provoke a reaction from the Israelis not only there, but perhaps even on a much wider scale."
Israeli Major-General Avraham Rotem said one of two scenarios could unfold. The first one - which everyone wants but is doubtful - is that peace will prevail at the border.
More likely is a developing cycle of violence, he said. There was a very real possibility of an outright Hizballah attack.
Another possible scenario could see a lone gunman - not sent by an organization or government, but with a grudge against Israel -drive to the border and shoot or throw a grenade through the window of an Israeli home.
If it were to happen once, Rotem said, Israel may accept that it was a one-off mistake. But if it happens several times, which it could, Israel would be forced to retaliate. Hizballah would react and Israel would respond, he predicted.
"The cycle will start ... The probability is very high that it will happen," said Rotem, a former commander of Israel's armored corps. "The situation is very sensitive. The border is completely not ready [for the new situation]."
If Israel was forced to respond to an attack, Rotem predicted, the international backing Barak believes Israel would have would quickly evaporate if there were the inevitable civilian casualties.
On the Lebanese side no authority was in place, he noted. Some villages were held by Christians, some by another ethnic minority, the Druze, some by Hizballah, and some by Amal, another Islamist militia. "Everybody [goes] everywhere with cars and guns. It's worse than the wild west," he said.
On Israel's side of the border, Rotem said, there were no fortifications and no military procedures yet. It may take several more months to put the situation in order.
"I'm sorry to say we must have a miracle that the situation will hold. If we start fighting, the sky is the limit."
Rotem, who claims to have favored a unilateral withdrawal from Lebanon for years, said Israel had "lost control" in its retreat.