NEW YORK // The US navy has announced that it will be pulling its sole aircraft carrier out of the Gulf this autumn – leaving the region without a naval strike force for the first time in seven years.

The absence of an aircraft carrier in the Gulf just as the Iran nuclear deal is expected to come into effect this autumn has drawn criticism from some US legislators. But analysts say the short-term gap is not militarily significant and the United States still has a huge amount of firepower stationed in the region to deter Tehran and carry out air strikes against ISIL.

The Obama administration has used its naval power in the Gulf, spearheaded by the aircraft carrier USS Theodore Roosevelt, as a crucial element of its bid to reassure GCC allies over its commitment to countering Tehran. In April it deployed the carrier to block Iranian ships from delivering weapons to Houthi rebels in Yemen.

Until recently the Pentagon required the US navy to keep at least one carrier in the Gulf at all times, with an overlap period between any replacement. But that requirement was replaced with new guidelines that allowed periods of no carrier presence.

The USS Theodore Roosevelt will leave the Gulf sometime in October, and be replaced with another carrier about two months later. Military officials said the gap was a result of badly needed maintenance across the US navy’s 10 carriers, combined with strains on military budgets and a growing demand for carriers in the Asia Pacific, where maritime tensions with China have increased.

“Due to a lot of maintenance and other rotational things the navy is doing with aircraft carriers, they just didn’t have one to relieve Theodore Roosevelt on time,” said an officer with US central command (Centcom), which coordinates military policy in the Middle East. “They notified us of that and we have the plans in place to mitigate for this”, he said, adding that “we will have an aircraft carrier back in the Gulf” soon.

“I wouldn’t say that just because we don’t have one that that lowers or changes the necessity to have one,” the Centcom officer said.

It is unclear whether the Pacific will be prioritised in the future and whether there may be more frequent absences of aircraft carriers in the Gulf. Where to deploy carriers “is always continuously being assessed by the combatant commanders,” said a US navy official. “I don’t know what they’re going to come up with for requirements for the future.”

There have been such gaps before, but not for at least seven years. Meanwhile, the gap scheduled to begin in October comes at a time of heightened anxiety in the Gulf over the implications of the lifting of sanctions on Iran and US commitments towards the region.

The move has been criticised by some in Washington. “We have 11 active nuclear aircraft carriers today in the United States navy,” said retired Admiral James Stavridis, the supreme allied commander of Nato until 2013, counting a carrier that is to be inducted soon.

“It is hard for me to understand why we cannot manage a fleet of that size to maintain an aircraft carrier at all times in regions as dangerous as the Arabian Gulf,” he said in a recent radio interview.

Speaking at the nomination hearing for the incoming naval chief last month, Republican senator John McCain said that the “absence of a carrier doesn’t authenticate a commitment” to Gulf allies.

Some analysts say the timing of the gap, even if one is unavoidable, is another misstep by the Obama administration in effectively communicating its Middle East policies, but others say Gulf officials are not overly concerned about the issue. “Gulf leaders are not paranoid and fixated on every US military move,” said Bilal Saab, an expert on US-GCC military affairs at the Atlantic Council think tank.

Navy fighter jets, many flying from the carrier, conduct around 20 per cent of missions against ISIL militants in Iraq and Syria, and US military officials said this will be offset by the opening of Turkey’s Incirlik airbase for bombing missions, and by the contribution of coalition countries.

The naval chief nominee, Admiral John Richardson, said that the temporary carrier absence would be “mitigated” by fighter jets stationed at airbases in the region. And, according to Centcom spokesman Lt Cmdr Kyle Raines, “Centcom continually reviews its theatre force requirement ... to ensure we have the force presence necessary to adequately address our ongoing commitments, mission requirements, and threats in the region”.

But Adm Richardson added during his nomination hearing that “without that carrier there will be a decrement in our capability there”.

The carrier is accompanied by a carrier group that includes a guided missile cruiser, destroyer, attack submarine and other vessels, and they typically leave with their carrier when it is rotated out, but not always, said the navy official.

While the carrier is the most powerful naval asset and a potent deterrent – essentially a US airbase that can be positioned just off an adversary’s coast – it does not carry out the day-to-day aspects of maritime security in the Strait of Hormuz and sea lanes crucial to the flow of Gulf oil.

In April, the US navy released plans to increase the number of ships in the region from 30 to 40 in the next five years, though this could be affected by ongoing budget cuts. In same month, the Pentagon announced that US warships would accompany American and potentially other countries’ commercial ships transiting the Strait of Hormuz after Iranian naval forces intercepted an oil tanker. This was later discontinued but an increased presence in the strait continues.

“As far as I can tell, the American commitment to the Gulf’s maritime security is as robust as it has always been,” said Muath Al Wari, an analyst of Gulf policy at the Centre on American Progress think tank.

The criticism from Mr McCain and other US legislators comes as the partisan fight over the Iran nuclear deal intensifies ahead of a likely vote next month, and as some are pushing for an end to defence budget cuts and new increases, both of which make the carrier gap an issue ripe for political jockeying.

Despite this, analysts said it does not represent a strategic shift and would not significantly change the overall US military posture in the region. “This means absolutely nothing,” said Mr Saab. “I realise some people will want to make a big deal out of it, but it’s not even politically significant, let alone militarily ... there is plenty of US firepower to go around in the Gulf.”

tkhan@thenational.ae