Ehud Barak has always prided himself on his intellect as much as his fighting ability. So when the Israeli Defence Minister launched Operation Cast Lead against Hamas on Saturday the offensive was meticulously planned. The targets in Gaza had been selected after months of intelligence gathering. Hamas leaders were taken by surprise. The timing was chosen to coincide with the Christmas season, when many world leaders are on holiday and the international response would be muted.

Now, however, Mr Barak, a former Prime Minister and special forces commander, faces the real test of his leadership as he begins the next, more dangerous, phase of his campaign.

Hamas has recovered from the initial attack. Its leaders are safely hidden away. It has been able to continue firing dozens of rockets into Israeli cities. Its main fighting force, of some 15,000 men, is intact and the group is preparing to defend the Gaza Strip from an Israeli ground offensive. Outrage abroad at the high civilian death toll and the growing humanitarian crisis facing Gaza’s population is growing by the hour. Poor weather is making it harder for the air force to fight and to provide air cover for a potential ground assault.

Foremost in the minds of all Israeli leaders is the fiasco of the Lebanon war in July 2006. Ehud Olmert, the Prime Minister, launched the attack in response to a provocation from Hezbollah, Lebanon’s Shia Muslim militia. After weeks of aerial bombardment and a tentative ground offensive, Israel was forced to withdraw, leaving its opponent strengthened and Hezbollah’s reputation in the Arab world enhanced.

With that in mind, what options does Mr Barak have to avoid repeating the mistakes of 2006?

First, he could resume the policy of targeted killings of Hamas leaders employed by Ariel Sharon in 2004 against Sheikh Ahmed Yassin and his successor, Abdel Aziz Rantisi. The most likely targets are Mahmoud al-Zahar, Hamas’s hardline Foreign Minister, and Ismail Haniya, the Hamas leader in Gaza. Both are now in hiding and well protected. Second, he could try to limit the range and disrupt the launch of Hamas rockets by sending ground forces on a limited incursion into northeastern areas of the Gaza Strip, probably Beit Lahia and Beit Hanoun. This would inevitably lead to more Palestinian civilian casualties and Israeli military losses, but it could relieve the pressure on southern Israel.

Third, the Israelis could reoccupy the Philadelphi strip between the southernmost point of Gaza at Rafah and the Egyptian border. This is the area through which Hamas has been smuggling weapons through a network of tunnels. If Israel can disrupt the supply, it could make it harder for Hamas to sustain a fight.

Finally, the Israelis could attempt to reoccupy the entire Gaza Strip, root out Hamas suspects and destroy their infrastructure. This would probably cost the lives of thousands of Palestinian civilians and hundreds of Israeli soldiers. It would also risk triggering a broader conflagration in the region with Hezbollah and Iran, and lead to concerted action by the international community.

For now, Mr Barak is probably contemplating more modest steps. Whatever he chooses, he knows that the stakes could not be higher for his political career and the fate of his Labour Party, both languishing in the polls before elections on February 10.

The Israeli public so far have supported the offensive against Hamas. But, as the 2006 Lebanon war showed, Israelis will quickly turn against any commander who fails to deliver victory.

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