Major Mariam al-Mansouri, a female pilot with the UAE air force, played the starring role in a publicity stunt last month when she was photographed in the cockpit of the F16 fighter she had flown in the first wave of US-led attacks on targets of the Islamic State in Syria (Isis).

Thumbs up and beaming for the camera, it was a striking image that combined empowered Muslim women, the Arab fightback against jihadi extremism – and the pride of the small but wealthy Gulf state that is flaunting a new-found assertiveness and promoting its political agenda in a region in profound turmoil.

Operating from the al-Dhafrah airbase in the desert south of Abu Dhabi, Mansouri and other Emirati pilots have flown more combat sorties than any of the other four Arab participants in Barack Obama’s campaign to destroy Isis. Precise figures remain secret and the communiques issued by US central command, which initially mentioned individual contributions by Saudi Arabia, the UAE, Jordan, Bahrain and Qatar, now only refer collectively to “partner nations” in Operation Inherent Resolve. Diplomats also hint that only a handful of Arab aircraft are involved and that the number of missions is already declining. The symbolism, in any event, probably counts for far more than any military impact.

Still, the UAE’s leading role in the war on Isis is of a piece with its wider ambitions in a Middle East transformed by the Arab spring. Egypt has been weakened by turmoil since the overthrow first of Hosni Mubarak and then of the Muslim Brotherhood’s Mohamed Morsi. Turkey is disliked by conservatives for backing Islamists, while Syria and Iraq are ravaged by bloodshed and sectarianism. Saudi Arabia, the autocratic Sunni giant of the Gulf, is slow, cautious and led by ageing royals.

Dubai, UAE, seen from the Burj Khalifa skyscraper. Photograph: EmmePi Travel / Alamy/Alamy

The Emiratis, by contrast, are dynamic, confident and unapologetic – adding plans to send an unmanned space probe to Mars to accomplishments that include the world’s tallest building and largest indoor ski resort. “Now they are sticking their heads above the parapet,” said a western diplomat. “They are highlighting their successful model and they want to counter the Muslim Brotherhood line that the Islamists are the solution.”

Emiratis have deftly woven themselves into the fabric of US defence strategy. UAE forces serve in Afghanistan – the only Arab state to do so. But they operate independently too. In August UAE aircraft based in Egypt bombed Islamist targets in Libya – though the operation was never officially avowed, a practice borrowed from the Israelis (with whom they are said to maintain discreet contact). Its F-16E/F Desert Falcons are even more advanced than those in service with the US – in part because the UAE invested millions in R&D. It wins praise from American officials who note the recent introduction of conscription and have nicknamed it the “Sparta” of the Gulf – a catchy if reductionist label.

“Whether one agrees with it or not, the UAE’s policy is the most coherent of all the Gulf states,” argues Emile Hokayem of the International Institute for Strategic Studies. “This small country has gained a seat at the table by developing serious military capabilities. Compared to others in the Gulf, there is unity of purpose and effort in the Emirati national security system. It helps that the big domestic issues, notably succession, have been sorted out.”

Fighting Islamists at home and abroad – and thus supporting fellow autocrats – is the centrepiece of the official Emirati world view as laid down by Mohammed Bin Zayed Al Nahyan, the crown prince, and articulated by Anwar Gargash, minister of state for foreign affairs. “Instead of being moderated through engagement, so-called moderate Islamists are increasingly being drafted into the ranks of radical groups,” Gargash declared at the inaugural session of the recent Abu Dhabi Strategic Dialogue – an event that attested to the country’s agenda-setting ambition.

The UAE, the UK’s second biggest trading partner in the Arab world, was instrumental in persuading the British government to conduct a controversial review of Brotherhood activities – apparently hoping it would lead to proscription.

Emirati opinion-formers sing the same tune on this issue – dismissing the argument that outlawing Islamists who embrace parliamentary democracy and shun violence risks leaving a vacuum that will be filled by jihadis such as al-Qaida and Isis. “It is true that the Brotherhood is not the same as Isis,” concedes Mohammed al-Otaiba, editor of the National, Abu Dhabi’s government-owned English language daily. ”But the concern is that if the MB came to power you would get a larger Isis element. And in the end the MB does not deliver. People in the UAE are happy with the way things are.”

Emirati citizens – officially 18% of the country’s total population – enjoy the fruits of high economic growth, free education, generous scholarships and health care. Sheikhs can be petitioned and a federal national council has limited powers. But political parties are banned. The Brotherhood was purged in the 1990s and the conviction of 69 Islamists and others on charges of seeking to overthrow the government was criticised harshly by human rights groups, though not by western allies. Social media is closely monitored and dissidents are routinely detained. Treatment of migrant labour attracts regular censure from NGOs.

The UAE’s assertiveness, suggests Mishaal al-Gergawi, who runs the Delma Institute thinktank from high up in one of Abu Dhabi’s many glittering towers, is driven by its new-found capacity to participate in global as well as regional affairs. The other factor is its no-holds-barred competition with Qatar – the maverick neighbour that has done so much to champion the Brotherhood. Both countries helped rebels fighting to overthrow Muammar Gaddafi of Libya in 2011, but Qatar backed Islamist militias while the Emiratis supported rival nationalists. The mysterious air strikes on Tripoli in August took their hostility to a new level.

Emirati involvement in Egypt has also been driven by rivalry with Qatar, whose al-Jazeera TV became an outspoken cheerleader for Morsi and the Brotherhood and continues to highlight the crackdown by President Abdel Fatah al-Sisi – who is lionised in Abu Dhabi. UAE media and PR firms focus intensely on exposing and countering Doha’s influence. The ugly diplomatic row that turned the rest of the Gulf Cooperation Council against Qatar has cooled, but it is far from over.

With the Saudis, the Emiratis have given billions of dollars to bail out the Egyptian economy and promote reforms.

“Jobs and growth are the most effective safeguards against radical ideologies and sectarian hatred,” said Gargash. Al-Gergawi goes further: “If the UAE succeeds in turning Egypt around the multiplier effect will be enormous,” he said. “It’s THE bet. We’re going all in.”

Aversion to Islamism in all forms has meant that UAE policies towards the war in Syria have differed from those of its neighbours. The Qataris and Saudis, individuals and governments, both spent vast amounts funding Islamist groups, some of which morphed into Isis over time. The Emiratis want Bashar al-Assad to go – but not at any price; they have backed only moderate opposition fighters approved by the US and other western countries.

Emiratis are more trusting of the US than the Saudis. But an undercurrent of concern about Obama’s determination, the limitations of his strategy, the risk of a Sunni backlash and his bid for US rapprochement with Iran is clearly audible – even as Mansouri and her fellow pilots are bombing the jihadis.

“You look at the Americans and you do wonder what they are going to do next,” said al-Gergawi. “Two hundred thousand people have already been killed in Syria and then four westerners are beheaded and they start to fight Isis. The difference between Bashar and Isis is that he doesn’t upload YouTube videos. It’s incredibly upsetting for the UAE to have to attack Arabs. It’s a little bit challenging. But what else are we going to do?”