— Britain on Friday became the latest nation to join the U.S.-led air campaign against Islamic State militants, with Parliament voting overwhelmingly to authorize attacks in Iraq — though not in Syria.

The vote brings Britain into the air campaign belatedly, some seven weeks after the United States first began carrying out strikes. Prime Minister David Cameron, scarred by a humiliating defeat last year when he sought permission to launch strikes against the government of Syrian President Bashar al-Assad, waited this time until he had a clear consensus of support.

Cameron got that backing Friday, with the leadership of all three main parties spearheading a 524-to-43 House of Commons vote endorsing Cameron’s plan to deploy British fighter jets to the skies above Iraq.

Still, there was opposition from the backbenches. Some hawkish members of Cameron’s own party insisted that airstrikes in Iraq would be meaningless unless the campaign was broadened to include Syria. There was also resistance from dovish members who insisted that the country had not learned the right lessons from more than a decade of misguided combat in Iraq and Afghanistan.

But Cameron argued that the Islamic State was impossible to ignore given the threat it poses to Britain.

“This is not a threat on the far side of the world. Left unchecked, we will face a terrorist caliphate on the shores of the Mediterranean and bordering a NATO member, with a declared and proven intention to attack our country and our people,” Cameron said as he opened a full day of debate.

Cameron and others who support airstrikes were quick to differentiate Friday’s vote from the last time the British Parliament authorized military action in Iraq, in 2003. Cameron stressed that there would be no boots on the ground and said the air campaign would be marked more by “patience and persistence” than “shock and awe.”

The vote clears the way for Washington’s closest ally to deploy six Tornado jets to carry out strikes on Islamic State targets in Iraq as early as Friday evening, though it is considered more likely that the attacks would begin over the weekend.

The British contribution is modest, representing only a third the number of jets that flew over Libya during the 2011 campaign against Moammar Gaddafi’s government. But it is similar in size to that of other nations that have joined the coalition against the Islamic State, including France, the Netherlands, Belgium and Australia.

Five Arab nations have also contributed — Saudi Arabia, the United Arab Emirates, Jordan, Bahrain and Qatar.

While the British public was divided over joining the air campaign when the United States first launched strikes last month, opinion has solidified in favor of the idea in recent weeks — especially after Islamic State militants executed two American journalists and a British aid worker. At least two other Britons are known to be held by the group and have been forced to appear in Islamic State propaganda videos.

European counterterrorism officials have expressed deep concern that the Islamic State will try to carry out attacks on Western soil, perhaps employing some of the estimated 3,000 Europeans who have traveled to Iraq and Syria to fight with the organization.

Cameron suggested Friday that there would be a strong case for expanding Britain’s air campaign to Syria — but said that would require a separate debate.

Labor Party leader Ed Miliband has maintained that he would like to see a United Nations resolution authorizing strikes in Syria before he will back such a move. Unlike in Syria, the government in Iraq has welcomed Western intervention.