US officials have maintained that the military coalition will secure navigation routes between Yemen and Iran, adding another layer of complexity to the troubled waters of the Middle East.
The US wants to forge a new alliance with other nations over the next two weeks precisely to 'safeguard' waters off Iran and Yemen.
US Marine General Joseph Dunford explained on Tuesday that Washington has reached out to "a number of countries" to stitch up a coalition that would "ensure freedom of navigation both in the Straits of Hormuz and the Bab al Mandab".
Tensions between the US and Iran are already high with reports of oil tankers being attacked in the Gulf on two separate occasions in the last two months. The US was quick to blame Iran, threatening the Shia-majority country with war. The situation escalated further with Tehran shooting down an American drone in its airspace. But amidst the shrill rhetoric, America's regional ally the UAE, an archrival of Tehran, said "no country could be held responsible" for the alleged attacks until a strong piece of evidence is produced against the accused.
The episode however, was yet another sign of deteriorating US-Iran ties in light of President Donald Trump's withdrawal from the landmark nuclear deal signed between his predecessor Barack Obama and Iranian Prime Minister Hassan Rouhani. The backtracking from the deal triggered a new round of hostility between Washington and Tehran.
So how will an international alliance for Gulf waters look like?
The plan, which has only been finalised in recent days, proposes that the United States would provide command ships and lead surveillance efforts for the military coalition. Allies would patrol waters near those US command ships and escort commercial vessels with their nation’s flags.
"I think probably over the next couple weeks we'll identify which nations have the political will to support that initiative and then we'll work directly with the militaries to identify the specific capabilities that'll support that," Dunford, Chairman of the US Joint Chiefs of Staff, said.
The US would provide "maritime domain awareness and surveillance", while ships would be escorted by the nations whose flag they carry, the general said.
Why is the US so concerned with the Gulf shipping route?
Almost a fifth of the world's oil passes through the Strait of Hormuz in the Gulf, and Iran has long threatened to close it if the country were unable to export its oil.
Previously, Iran and Iraq engaged in one of the longest ever tanker wars in the late 20th Century.
Both countries weaponised the sea to damage each other’s economy, in particular, their oil industries, through a war of economic attrition.
In the1980s, Iraq and Iran attacked international ships en route to each other's ports in order to halt oil exports which funded the war effort of both sides.
During the first three years of the war, Iraq demonstrated naval aggression, but after 1984, Iran started to counteract. By the end of the war, Iraq had attacked 283 ships heading to Iran versus 168 by Iran.
The conflict took on an international dimension when ships sailing under more than 38 different flags were attacked. The US was eventually drawn into the war after one of its vessels came under an attack. The US navy effectively destroyed the Iranian navy, reducing its operational capacity a great extent.
Yemen, the new element
Although US officials argued that the naval alliance is meant to safeguard the Strait, there's another element to it and that is to bolster security in the Bab al Mandab off Yemen.
The United States, as well as Saudi Arabia and the United Arab Emirates, have long anticipated attacks by Iran-aligned Houthi fighters in the Bab al Mandab waterway, which links the Red Sea with the Gulf of Aden and the Arabian Sea.
Bab al Mandab also carries a strategic element, with nearly four million barrels of oil shipped daily from its port to Europe, the US and several other Asian countries.
A dilemma amongst the US allies
On May 2, the US sent an aircraft carrier strike group and B-52 bombers to the Gulf because of what they described as "troubling and escalatory indications" by Iran. In response to the sanctions, Iranian President Hassan Rouhani said Iran will scale back its commitments under the nuclear deal, including by allowing its stockpile of low-enriched uranium to increase.
The incidents of oil-tanker attacks and US drone shooting by Iranian forces followed.
Although the regional allies have almost always wanted Washington to take a tough line against Iran, they also seem to be unsure whether to push the US for an all out war or to favour negotiations.
According to the Washington Post, there is "little consensus" among the US-friendly Gulf nations on "how best to confront Iran".
“Trump is again questioning the US role as security guarantor in their region. The gulf countries are in a tight spot,” the newspaper quoted Henry Rome, a Middle East analyst, as saying.