Triple suicide bombings in Jordan this week marked a breakthrough for Islamic guerrilla leader Abu Musab Zarqawi in his efforts to expand the Iraqi insurgency into a regional conflict and demonstrated his growing independence from the founders of al Qaeda, according to Arab and European intelligence officials.

Zarqawi, 39, has sought for years to overthrow the monarchy in his native Jordan. But since he emerged over the past two years as the best-known leader of the insurgency in Iraq, his success in rallying Islamic extremists from other countries to fight U.S. forces there has enabled him to extend his reach and influence, officials and analysts say. His guerrilla network, they say, has established roots in Syria, Lebanon, Saudi Arabia and Iran.

"This is really alarming, if Zarqawi is able to carry out these kind of attacks in Jordan and if Iraq is able to become the headquarters for terror attacks in the region," said Mustafa Alani, senior policy analyst for the Gulf Research Center in Dubai. "We're talking about the emergence of another Afghanistan."

Some terrorism analysts and officials say Zarqawi has already eclipsed al Qaeda's founder, Osama bin Laden, in terms of prominence and appeal to Islamic radicals worldwide. Both want to establish a new Islamic caliphate in the Middle East but have clashed over tactics, such as whether it is advisable to avoid targeting Muslims.

While bin Laden has been on the run for the past four years, largely cut off from the outside world, Zarqawi has attracted hundreds if not thousands of fighters to Iraq and has avoided capture despite the presence of as many as 150,000 U.S. troops. He also has raised his profile by embracing merciless tactics, including videotaped beheadings and suicide attacks on civilian targets, such as the bombings in Amman that killed nearly 60 people at three hotels Wednesday night.

Jordanian officials said Saturday that Zarqawi's group had carried out the attacks, employing three suicide bombers from outside Jordan. A day earlier, the group asserted in an Internet statement that the bombers were four Iraqis -- three men and a woman.

"He's fashioned himself as the most important competitive force to al Qaedism," said Bruce Hoffman, a terrorism expert and director of the Washington office of the Rand Corp., a California-based research group. "For Zarqawi, Iraq is a means to an end, rather than an end to a means. His road runs through Baghdad, but it doesn't stop there. It goes on to Amman, Tel Aviv, Riyadh and perhaps even Western Europe."

Although he has formed an alliance with al Qaeda, Zarqawi has always worked as an independent operator. He met bin Laden in Kandahar, Afghanistan, in 1999 and received some financial support from al Qaeda, but established a separate Afghan training camp for Jordanian fighters.

Last year, in a letter to bin Laden that was intercepted by the U.S. military, Zarqawi pledged his loyalty and changed the name of his Iraq-based Monotheism and Jihad network to al Qaeda in Iraq. But he also has squabbled with other al Qaeda leaders over tactics, strategy and fundraising.

In July, al Qaeda's deputy leader, Ayman Zawahiri, wrote a 16-page letter to Zarqawi that gently scolded him for kidnapping Arabs, killing rivals and sponsoring indiscriminate attacks that resulted in the deaths of innocent Muslims.

"The strongest weapon that the holy warriors enjoy is popular support from the Muslim masses," Zawahiri wrote. "In the absence of this popular support, the Islamic warrior movement would be crushed in the shadows, far from the masses who are distracted and fearful."

The U.S. government and several European intelligence agencies have concluded that the letter is genuine, although some independent researchers have expressed doubts about its authenticity.

Other erstwhile allies of Zarqawi have expressed similar misgivings about his approach. Abu Mohammed Maqdisi, a radical Jordanian cleric who became Zarqawi's mentor when both were imprisoned in the late 1990s, said in August that Zarqawi was hurting their shared cause by launching suicide attacks that often killed Muslim women and children "but barely one or two occupier Americans."

Maqdisi, also known as Isam Mohammad Taher Barqawi, said Zarqawi was making a serious tactical mistake by targeting Shiite Muslims. Shiites make up a majority of the population in Iraq, but Zarqawi, a Sunni, regularly denounces them as apostates.

"I am not ashamed or embarrassed at all to say that I do not sanction it, support it or approve it," Maqdisi told al-Jazeera television in July. "You blow up a Shiite mosque and the Shiites blow up a Sunni mosque and the circle of conflict shifts from fighting the occupier enemy. It becomes communal fighting between two factions who should be in one camp against the occupier."

Zarqawi has ignored the advice and has continued to target Muslims suspected of helping U.S. forces, the Iraqi government and other foes. On Friday, his network posted an Internet statement asserting that it had executed six North African contractors in Iraq accused of "supporting the infidels."

The same day, after thousands of Jordanians took to the streets to protest the Amman bombings and to denounce Zarqawi, his organization posted another statement. It said the Amman hotels were chosen as targets because they were known gathering places for intelligence agents from the United States, Israel, Jordan, Egypt and Saudi Arabia.

But the statement also rebuked the protesters, calling them hypocrites for remaining silent about Muslims killed or wounded by U.S. forces in Iraq. "By God, we did not see from them at any time sadness about Muslim spilled blood every day" in Iraq, it read.

Despite their differences, Zarqawi and the founders of al Qaeda share an overarching goal: to unify all Muslim lands under a caliphate, or a single theocratic state.

Since the late 1990s, bin Laden and al Qaeda strategists have sought to accomplish that primarily by attacking what they refer to as "the far enemy" -- the United States, Europe and other nations that have forged alliances with the secular states of the Middle East. The Sept. 11, 2001, attacks in the United States, the train bombings in Madrid in March 2004 and the subway bombings in London last July all were designed to press Western powers to withdraw military forces from the Middle East and cease their support for countries such as Egypt, Jordan and Saudi Arabia.

Zarqawi has carved his own path, however, by taking a more direct approach and fighting closer to home, both in Jordan and in Iraq. In contrast with al Qaeda's penchant for airplane hijackings and other catastrophic plots, Zarqawi operates more as a guerrilla fighter, relying on roadside bombs, kidnappings and suicide attacks.

The Amman bombings were not the first time Zarqawi had launched an attack on Jordan from his base in Iraq. In August, his followers fired Katyusha rockets at U.S. ships in the Red Sea port of Aqaba, but missed.

In April 2004, the Jordanian government said it had disrupted a Zarqawi plot to blow up the headquarters of the Jordanian intelligence service. It said the plot involved truckloads of chemical-laced explosives that could have created a gas cloud with the potential to kill 80,000 people.

Unlike bin Laden, Zarqawi has also placed a high priority on fighting Israel and has tried -- unsuccessfully -- to organize bombings and suicide attacks there, according to Arab intelligence sources.

Wednesday's attacks in Amman were intended to be an indirect strike against Israel, analysts and counterterrorism officials said. In a statement asserting responsibility for the bombings, Zarqawi's network called the hotels "playgrounds for Jewish terrorists" and said they were frequented by Israeli intelligence agents.

One reason Zarqawi has pledged to overthrow the Jordanian monarchy is that it signed a peace treaty with Israel. In his bid to destabilize Jordan and pressure U.S. forces to leave Iraq, Zarqawi hopes to weaken Israel as well, counterterrorism officials and analysts said.

"The real goal of Zarqawi is to banish Israel from the region, or even annihilate Israel," Ernst Uhrlau, intelligence coordinator for German Chancellor Gerhard Schroeder, said at a security conference in Berlin on Thursday. Uhrlau characterized the Amman attacks as an attempt by Zarqawi "to demonstrate the ability to act against Israel from inside Jordan."

European security officials have become increasingly worried that, given his increased stature in the Middle East, Zarqawi might begin to shift his focus to the so-called far enemy as well.

Last month, four Zarqawi acolytes were convicted in Duesseldorf of plotting attacks against Jewish targets in Germany in 2002. Testimony showed that some of them were in regular phone contact with Zarqawi and raised money on his behalf.

The presiding judge, Ottmar Breidling, said there was no doubt who was behind the plots. "Abu Musab Zarqawi should also be sitting on the defendants' bench," he said in court.

Zarqawi has been sentenced in absentia to death for other terrorism plots in Jordan.

Some European intelligence officials said they fear that Zarqawi is becoming a galvanizing figure for Islamic radicals and could eventually take the place of bin Laden as the symbolic head of the movement.

August Hanning, president of Germany's foreign intelligence service, said there were signs of increased numbers of Islamic extremists going to Iraq from Europe to fight for Zarqawi, not because his network had recruited them directly, but merely because his success inspired them to join.

"He functions as a role model. There are groups that believe it is a great honor to be able to carry out attacks in his name," Hanning said at the Berlin conference Thursday. "We have seen how numerous groups, who -- on their own initiative -- have tried to make contact with Zarqawi to work together."

Abu Musab Zarqawi is shown in undated photos released in 2002 and 2004.