Over the past year, British Prime Minister Gordon Brown was widely viewed as a walking political corpse. Lacking the charisma and luster of his predecessor, Tony Blair, and with an electorate tired of Labor leadership, he began falling dramatically in the polls and appeared more and more to be a caretaker leader, who was destined eventually to hand the keys to 10 Downing Street over to the Tories' David Cameron.

When Brown visited Israel in July, the media completely ignored him. Barack Obama was here the same day, and no one was interested in a tourist from London whose future appeared to be about as bright as that of his host, Ehud Olmert.

Then the financial crisis hit. When other leaders and bank chairmen groped about in the fog, unsure of how to respond to the crash of the markets and assorted financial institutions, Brown presented a bailout plan: partial nationalization of the banks by way of a financial injection from the state.

His foreign colleagues rushed to adopt the model, Brown was praised as the world's savior, and he even began to rise in the polls. If Brown's plan succeeds, history will remember Blair as a mere doormat who marched along with George W. Bush into an unnecessary war in Iraq, and Brown as the Winston Churchill of the 2008 crisis.

Brown's turnaround provides an important lesson in leadership. In business schools, they teach that leadership is not a quality one is born with - a certain charisma given to a chosen few - but the ability to cope with unforeseen change. Everyone is afraid of change and surprises. Few know how to convert them into opportunities, to leverage them into achievements. That is the manifestation of leadership, and that is what Brown did, just as Churchill did in World War II.

As in Britain, so in Israel. David Ben-Gurion was a world champion at leveraging change. After the Holocaust, he understood that the world's mood had changed, and that the powers would support the creation of a Jewish state in the Land of Israel.

Ben-Gurion exploited the French quagmire in Algeria to strike at Egypt's Gamal Abdel Nasser and get French assistance in building a nuclear reactor. The magic ran out toward the end of his term, however. Ben-Gurion struggled to deal with a rebellion in his party over the Lavon Affair, and when John F. Kennedy applied pressure on him to shut down the nuclear reactor in Dimona, he simply cracked and left office.

The records of his successors are mixed. Levi Eshkol took advantage of Kennedy's assassination to complete the nuclear project, but when the crisis broke out that led to the 1967 Six-Day War, he hesitated and was eventually forced to hand the defense portfolio over to Moshe Dayan.

Golda Meir understood the changes taking place in America with the rise of Richard Nixon to power, and sought and received his tacit recognition of Israel's nuclear capability. But her total failure to recognize the changes taking place in Anwar Sadat's Egypt were responsible for bringing Israel to the disaster of the 1973 Yom Kippur War.

Menachem Begin leveraged the peace process with Egypt to fill the West Bank with settlements, and later the election of Ronald Reagan and the Iran-Iraq War to attack the Iraqi nuclear reactor. He failed in the invasion of Lebanon, however, because he failed to understand the transformation in the world's perception of the Palestinians from terrorists to victims.

Ehud Barak leveraged Bill Clinton's longing for a political legacy, but when the peace process he entered into failed and the second intifada broke out, he wavered between pursuing negotiations and a forceful response, and was ousted from power.

Ariel Sharon made use of the 9/11 attacks on America and the international outrage at Arab terror to crush Yasser Arafat and suppress the Palestinian intifada.

Olmert hoped to leverage the kidnapping of Israeli soldiers in south Lebanon to build up his own image as a determined commander, and advance his goal of evacuating settlements in the West Bank, but in the end was unable to realize either of these goals.

What does this say about Tzipi Livni? Like any other leader, she too will be judged by her ability to deal with changing conditions and to take advantage of them for her own benefit. Neither her past experience nor the record of her army service will determine whether she is fit to serve as prime minister, but rather the decisions she makes in response to the changes that take place around her - changes expected to accompany the U.S. elections, the economic recession, the Iranian nuclear program and those yet unknown. Will she feel the pressure and have difficulty making decisions, as claim her political rivals, or will she succeed in identify opportunities and operate with speed and determination?

Livni has shown an impressive ability to exploit changes and crises as opportunities to advance her career. The schism within the Likud and Sharon's subsequent illness placed her in the position of caretaker foreign minister, even though there were more experienced veteran politicians who could have filled the position instead.

Livni then took advantage of the Second Lebanon War and the Winograd Report that followed it to distance herself from Olmert and position herself as a leading candidate to head the government. She then leveraged Ehud Barak's mutiny after the Talansky Affair to place herself at the gates to the Prime Minister's Office. Should she win the position she so eagerly seeks, Livni will have to show the same skills on the national stage. That is her test.