EVERY FEW DAYS fiery rockets and explosions in the night sky remind Saudis of the war in Yemen. Missiles fired by the Houthi militia, a Shia group that overthrew the Yemeni government in 2015, are usually intercepted or fall harmlessly in the Saudi desert. But the volleys are evidence that, after three years of war and relentless air bombardment, the Houthis are undefeated. The range of their missiles has increased to reach Riyadh.

The detritus of the missile war is on display at the Officers Club in Riyadh, where the Saudis hold military briefings. The centrepiece is the wreckage of a Qiam missile. It bears rough weld-marks showing where it had been cut into more transportable pieces and later reattached. Parts bear the stamp of the Shahid Bagheri Industrial Group, an Iranian firm that is blacklisted by the UN. Such evidence of Iran’s missile-smuggling strengthens Saudi Arabia’s claim that the Houthis are an arm of Iran; it is also used as justification for the blockade of Houthi ports.

The war highlights the fear the Saudis and their allies have of encirclement by Iran and its allies, who sometimes boast of controlling four Arab capitals—Baghdad, Damascus, Beirut and Sana’a. Above all, Gulf states fear being abandoned by America.

For the Saudis, the Houthis are akin to Hizbullah, the Iranian-backed militia that dominates Lebanon, alarms Israel and props up the Syrian regime. Against the Houthis, the Saudis have mustered a coalition with the UAE, and smaller contributions from Egypt, the GCC and other Sunni states—and a variety of Yemeni militias. But the campaign has dragged on for longer than they expected, and talk of seeking a political deal is growing. “There is no military solution,” says one Gulf minister, “but we still need military pressure on the Houthis.”

The allies this month assaulted Hodeida, the last major Houthi port, despite the UN’s call to avert an attack that, it fears, could worsen what it says is already the world’s worst humanitarian crisis. Western officials fear that the longer the war goes on, the more Iran can entangle the Saudis at low cost to itself, and the more the Houthis become a fully-fledged Iranian proxy.

The war in Yemen was perhaps the first instance of Muhammad bin Salman’s instinct for forceful, if not reckless, behaviour. Another is the fortnight-long detention in Riyadh of the Lebanese prime minister, Saad Hariri, a longtime client of Saudi Arabia’s, who displeased the crown prince. He was eventually released as a result of international pressure.

Gulf leaders feel a profound frustration. They are richer than Iran, and have stronger alliances, yet they cannot beat Iran in the game of proxies. “The Iranian dollar is elastic—it stretches so far. Why do our dollars not do the same?” asks the Gulf minister. There are several answers. It is easier to undermine a fragile status quo than to keep it. Iran is focused, whereas Gulf states scatter their money among different groups. Iran has a foreign legion, in the form of the Revolutionary Guards’ Quds Force, that is good at building effective sub-state militias such as Hizbullah.

Worse, in the view of Gulf states, America is no longer a reliable protector. Relations with Barack Obama were particularly testy. His “pivot to Asia” was a shift away from the Middle East and its endless wars. In the view of Gulf leaders (and Israel) he forsook Hosni Mubarak in Egypt during the Arab spring, then tried to cosy up to Iran by signing a nuclear deal with the mullahs. The reality was more complicated, not least because the advance of Islamic State (IS) kept America fighting in Iraq and Syria.

Although Mr Trump had campaigned with anti-Muslim rhetoric, Arab leaders such as King Salman and Mr Sisi embraced him at a summit in Riyadh, where they clasped a glowing orb together (pictured). “Donald Trump is 100 times better than Obama,” declares the Gulf minister. Mr Trump does not have qualms about befriending strongmen. He sees Iran as a foe to be confronted, not a power to be accommodated. Gulf leaders hailed his move to abandon Mr Obama’s nuclear deal with Iran. Still, they worry about his commitment to confronting Iran. With IS weakened, Mr Trump said in March, “We’ll be coming out of Syria very soon. Let the other people take care of it now.”

Gulf leaders were scarcely charmed by his remark that “they wouldn’t last a week” without American protection. His covetous attention to their wealth, though useful, can be awkward. Pitching American weaponry to the Saudi crown prince at the White House in March, Mr Trump commented about one item costing $525m, “That’s peanuts for you.”

In 2017 Saudi Arabia became the highest military spender in the world after America and China. Even so, the Saudis’ military capabilities are questionable. They appear to have scored a coup in April with an air strike in Yemen that killed the Houthis’ second-in-command. More often, though, the air operations make the headlines because they prove inaccurate. Apart from a few advisers, the Saudi army has not deployed to Yemen.

By contrast, the small but hardened armed forces of the UAE have been honed with the NATO-led coalition in Afghanistan and are the speartip of the Saudi coalition in Yemen. The Emiratis have retaken Aden from the Houthis and Mukalla from al-Qaeda’s branch in Yemen. Like Qatar, the UAE has introduced military conscription. James Mattis, the American defence secretary, calls the UAE “little Sparta”. For Anwar Gargash, the Emirati deputy foreign minister, America’s strategy in the region is “in flux”. Gulf states, he says, understand they are living in an era of “multiple polarity”. They must act to defend their interests, and they must show America that they can be capable allies.

Increasingly, the Emiratis are pursuing their own war aims. They seem to be acquiescing in the break-up of Yemen, if not pushing for it, by forming an alliance with southern separatists. Their military deployment on the Yemeni island of Socotra, in the Gulf of Aden, infuriated the exiled Yemeni government that the coalition is supposed to be restoring to power. In Somalia, meanwhile, the Emiratis are building ports in the breakaway regions of Puntland and Somaliland.

Their objectives are murky. As a shipping hub for trade between Asia, Europe and Africa, the UAE has an interest in the safety of shipping lanes such as the Bab al-Mandab strait. And DPWorld, which runs the Jebel Ali port outside Dubai, has been diversifying by buying ports across the world. But, given the poverty and strife in Yemen and Somalia, investing in harbours there seems strange. Perhaps the UAE is gambling that harbours around the Horn of Africa may one day provide access to Africa’s interior. And ports on Yemen’s shore might become alternative hubs to Jebel Ali, shortening journeys and avoiding the narrow Strait of Hormuz—especially if war breaks out with Iran.

As they hedge their bets, Gulf states have kept quiet about Russia’s intervention in Syria even though, by supporting Bashar al-Assad, Russia is acting as the air force of the Shia axis that the Gulf leaders so fear. Moreover, Saudi Arabia has sought to woo Russia, buying weapons, signing defence-industrial agreements and striking an unprecedented deal in 2016 to cut oil output to drive up the price of crude. Perhaps the most intriguing diplomatic signals have been directed at the old enemy, Israel. Saudi Arabia now says Jews have a right to their own state. Bahrain says Israel has a right to defend itself against Iran. How long before Israeli and Gulf ministers start to meet openly?