Saddam Hussein, the 53-year-old absolute ruler of Iraq, may well go down in history as the man who provoked the first major crisis of the post-Cold War era -- one that threatened equally the interests of East and West -- as his troops rampaged through a Persian Gulf oil emirate

The invasion of Kuwait is the latest wild card to be be played by this brash and often brutal leader, whose tactics have terrorized his neighbors, incited the Israelis with threats of chemical retaliation and made the superpowers look like helpless giants.

How does he get away with it? In the Kuwait crisis, one answer may be surprisingly simple. Saddam Hussein does not always tell the truth.

Consider the chain of broken promises that preceded yesterday's invasion. In January, Saddam granted an audience to Sen. Arlen Specter (R-Pa.) and assured him Iraq wanted warm relations with the United States. Then came more revelations about Iraqi nuclear research. In April, Sen. Bob Dole (R-Kan.) led a group of senators to see Saddam,and once again the Iraqi professed goodwill to Bush and to America and complained of an Israeli conspiracy to smite him.

Last week, after Saddam had put his invasion plan in motion by moving tens of thousands of troops to the Kuwaiti border, he called in U.S. Ambassador April Glaspie and assured her this was a dispute within the Arab "family" and should not concern the United States, with which he wanted good relations. And he told a would-be mediator, Egyptian President Hosni Mubarak, that he had "no intention" of invading Kuwait.

Saddam is a man of peasant background who grew up in the heady and violent politics of Arab nationalism. He participated in Iraq's revolt against the last vestiges of monarchy and British colonial power on the Mesopotamian plain. He plotted assassinations and fomented violence, and in office he has perpetuated his rule with a mixture of secret-police brutality, Mafia-like family control of his government apparatus and financial patronage to favored elements of the armed forces.

Today, he is a modern Arab conqueror who is seeking to industrialize his society as a hedge against domination by his traditional enemy, Iran, and has built an arsenal of ballistic missiles and chemical weapons to deter his secondary enemies in Israel, Syria and elsewhere who would deny him his still undefined goals of power and influence in the Middle East.

Thursday's invasion belied a recent view of Saddam as a sober and mature ex-radical, ready to play a constructive and peaceful role in the Arab world.

The Saddam Hussein of "brotherly Arab cooperation" -- to resolve disputes and rebuild his war-torn country -- has been replaced by the Saddam driven to military conquest by political unrest at home, economic stagnation and a general frustration that "Arab cooperation" brought no relief from domestic problems.

Those problems include a disaffected military establishment, which handed Saddam his victory over Iran but then faced a painful demobilization and a restless population living in a sometimes abusive police state with few opportunities to travel to the outside world.

"In one stroke, he has done something about the money problem, he has found something for the army to do and his people are very happy to get Kuwait -- now they got something out of the war," said Laurie Mylroie, a Middle East scholar at Harvard University.

His challenge to the West, which has the military power ultimately to crush Iraq, is one of the most puzzling aspects of Saddam's invasion decision.

Said Mylroie, "No one thought he would do this. But he seems to prefer to take his risks with the outside world than at home."

Some U.S. military officials said yesterday that the Iraqi leader only moved after weighing the potential for a tough American response and concluding that the U.S. statements and naval exercises of the last two weeks were mere posturing and that the United States was not prepared to come to Kuwait's defense.

"There was not enough said in a firm enough way to stop him from moving," said one specialist.

"Saddam Hussein is a man with a large ego," Iraq specialist Phoebe Marr recently told a congressional hearing. "He is a shrewd politician and tactician, has a canny understanding of the political dynamics of his own society and is a survivor who has kept himself and his regime in power for 22 years in a country notoriously difficult to govern."

One Western diplomat who observed Saddam at close quarters for four years in Baghdad described him as "a consummate politician at the height of his powers."

When Saddam emerged from the Iran-Iraq war in late 1988, moderate Arab leaders who supported Iraq's war effort were enthusiastic about his power, maturity and willingness to contribute to the Arab cause. Saudi, Egyptian and Jordanian leaders argued that Saddam would work to cement his regional alliances because his Arab neighbors had saved him from defeat by Iran.

Whether he is now lashing out in frustration over domestic discontent or acting out a campaign to subjugate his Arab brothers and exert at least marginal control over the world oil market, Saddam has seized the world's attention as a dictator who twice in 10 years has invaded a neighbor to settle a score.

"This is what we get for being neighborly," said Kuwait's ambassador to Washington, Sheik Saud Nasir Sabah, whose country shared its treasury, port facilities and oil with Saddam during his war with Iran.

Saudi Arabia made similiar sacrifices, and yesterday Saudi officials were weighing whether to denounce Saddam and seek U.S. military protection or continue to do business with him in the climate of intimidation that now rules the region. "Somebody is going to have to stop him -- call his bluff," said Mylroie, who added: "After all, what lies between him and the Saudi oil fields?"

The turning point in Saddam's behavior lies somewhere in the first months of 1990, according to many experts. It could have been a crucial closed session of the Arab Cooperation Council in which he is said to have scorned the Kuwaitis by reportedly telling his shocked colleagues: "I need $30 billion, and if they don't give it to me, I'm going to take it from them."