Today the NYT is reporting that Iran’s strategy of targeting US bases in the region has been directly responsible for the resupply problems facing the USN. Now, we have long been aware of the great stresses placed on the US force projection into the region that the destruction of US radars and bases have posed. It was always a sort of domino strategy. Iran first systematically destroyed early warning radars near the Persian Gulf, which left US bases utterly vulnerable. Then the bases themselves were effectively dismantiled. That forced the US to withdraw westward to places like Jordan, but Iranian missiles followed them. US planes are now largely based in Israel or other similarly distant points. Amerikanets ably summarized the situation back on July 19:

Debasification

Iranian air war strategy

The US force in the region losing access to both the first and second lines of airbases available to it at the start of the conflict is a development with profound strategic and operational consequences. Depending on how you slice it, the number of airbases from which the US would likely conduct operations against Iran prewar was around 20. Without access to bases in Kuwait, Bahrain, Qatar, the UAE, KSA, and Jordan, that number will be cut to around five. This will compress hundreds of airframes into just a handful of tarmacs and runways, making it impossible to get those assets into the air in the time between early warning radars detecting an Iranian MRBM launch and that missile impacting its target in Israel. With more assets on the tarmac, the Iranians are much more likely to score hits. As the Pentagon moves more assets into the region to stage for a potential ramp-up in attacks on Iran, this issue will compound.

Enter a second asymmetry: the US Axis depends on aerial refueling to generate combat power, and the distance that makes Israeli bases safer to conduct operations from undercuts refueling missions. Tankers that could have met attack aircraft for refueling missions directly over their takeoff point at Al Udeid in Qatar, for example, will now have to fly over a thousand miles to reach the southern border of Iran, and even farther if they want to avoid dangerous airspace over Iraq. This puts stress on airframes, sucks up fuel, and reduces the number of refueling missions that can be flown. These distances become extreme when considering that tankers may have to meet attack aircraft launched from carriers operating as much as 1,700 miles away from Israel in the Arabian Sea. The retreat to Israel effectively divides the US forces in the region in two, splitting USAF assets in Israel from USN assets off the coast of Oman.

The key to the American air campaign has always been to degrade Iranian air defenses to the point that cheap and plentiful glide or even gravity bombs can be used against targets in Iran. Dwindling stocks of long-range cruise missiles make this a necessity. To accomplish this, American air forces have to conduct Suppression/Destruction of Enemy Air Defenses (S/DEAD) operations, which require long loiter times with aircraft remaining in the air to respond to ISR and emissions from air defense radars. These missions are exceptionally dependent on tanker support, so any degradation of US tanker operations in turn degrades American S/DEAD capabilities.

By all available evidence, the Iranian debasification campaign appears to be working. The US force in the region is likely incapable of generating the same combat power in its air operations against Iran as it could when the war started, and things are trending ever further in a negative direction. Even worse, there’s no clear solution on the horizon. The most obvious lever for American planners to pull is to accept more casualties and losses of personnel and airframes, but this is an unprecedented step the modern incarnation of the US military has never faced.

So nearly a month ago Trump’s empty threats had been exposed. Yes, the US was still able to launch strikes, but they were unsustainable beyond a few days, while Iranian retaliation is sustainable indefinitely. No doubt the military command has been telling Trump all of this, and Trump’s public pronunciamentos are empty gaslighting. All his eggs are now in the sanctions basket. Count on that to backfire against the US and its allies. Iran, backed by Russia and China (and other countries acting discretely) will outlast Trump—perhaps to 2029. But Iran is now shifting to an offensive posture, so Trump may find himself if an even tighter box.

This brings us back to the resupply problems facing the USN out in the Gulf of Oman, the Arabian Sea, and the Indian Ocean. Iran’s debasification strategy wasn’t confined to actual US bases in the Persian Gulf and westward. While radar was the priority target early on, they later struck at resupply facilities on the Gulf of Oman controlled by the UAE and Oman. That has forced US logistics to be pushed back all the way to Diego Garcia out in the Indian Ocean, 2200 miles distant from the Strait of Hormuz. But, Iran does have missiles that can reach Diego Garcia. The next phase of war may feature Iran’s new offensive posture may include determined attacks on USN ships—not just warning or harassing shots—as well as on Diego Garcia.

The Hormuz Letter @HormuzLetter

2h

BREAKING: The US Navy has shifted its main regional logistics hub 2,200 miles to Diego Garcia after Iran struck and fully destroyed the US Navy base in Bahrain early in the Iran war, directly contributing to the supply problems aboard the USS Abraham Lincoln, per NYT.

Iran subsequently struck Diego Garcia on March 20 with 2 medium-range ballistic missiles, with 1 falling short into the Indian Ocean and the other shot down by a US Navy warship, with a senior Iranian source familiar with the matter saying “more is to come” regarding strikes on the island. Both US carrier liberty ports (Bahrain + Emirati Fujairah on the Gulf of Oman) are within Iranian missile range.

Because of this logistics disruption, the carrier has set a historic record for time at sea, with sailors facing exhaustion, food shortages, water contamination, deteriorating conditions, supply shortages, lack of basic hygiene products, and poor-quality rations. Multiple sailors have tried jumping overboard and attempted suicide.

The USS Lincoln crew is also eligible for 5 “beer days” under Navy tradition, given time at sea, but no beer is available due to the shortages.

Now, the debasification strategy has been effective and well within Iranian capabilities largely because US bases are stationary targets. In that sense, the USN carrier groups have a signficant advantage because they are moving targets. That advantage is effective against both cruise missiles as well as ballistic missiles—for different reasons, in both cases. That doesn’t mean that USN ships are immune from attack, which is why they operate outside the range of Iranian coastal based cruise missiles. Probably the only country today that could plausibly—but still speculatively—present a real threat to USN carriers is China. The reason is that effective strike systems against these mobile and highly defended targets require very expensive and sophisticated spaced based ISR satellite systems. My take from these considerations, and those that follow in the limited quotes, is that Iran is probably best served by targeting the USN logistics chain—now including Diego Garcia—since these are stationary targets.

For a deep dive into the question of the feasibility of missile attacks against naval assets, Amerikanets has a very recent article. Here I quote only his conclusions, so follow the link if this subject interests you:

Why Hasn’t Iran Sunk an American Aircraft Carrier?

And what’s up with anti-ship ballistic missiles?

Before getting into the meat of this question, let’s get some caveats out of the way. The only thing we truly know, because it’s been confirmed in official statements by both sides, is that the Iranians have targeted US Navy assets. We don’t know if they’ve managed to hit an American ship, and there’s no strong evidence that they have, but we can be certain they haven’t sunk one. We don’t know how many anti-ship missiles and drones the Iranians have expended in their targeting efforts. We’ll avoid speculating on the possibility of American cover-ups of damage to naval vessels in this piece.

We can’t rule out that the Iranians are deliberately withholding a catastrophic strike. In this view, they could be limiting themselves to what are effectively warning shots to keep the American naval force in the Arabian Sea at a distance. This could make sense from a strategic perspective, as it would control the rate of escalation. Striking American bases in Jordan, for example, could plausibly be construed as lower on the Iranian escalation ladder than striking an American aircraft carrier, which is the enduring symbol of American military power. It’s long been speculated that the American government would be forced to respond to the sinking of an aircraft carrier with a retaliatory nuclear strike, though there is no evidence this is US military doctrine.

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It’s plausible that the Chinese possess a reliable, operational carrier killer today, and that they’re the only nation to ever have one. But this should be regarded as a holistic system, rather than just a particular missile. All the components in a highly sophisticated and staggeringly expensive chain reaching from the launcher on the ground to ISR satellites in space must work together.

So where does this leave the Iranians? First, none of this proves Iran hasn’t chosen restraint. What it does establish is that restraint is a more logical choice than it may at first appear. The Iranians don’t have the resources to create an integrated space-based ISR system like the Chinese have. Their coastal radars have suffered attrition. They’ve made massive leaps in missile technology, but this is just one link in a lengthy chain. Their best bet for the moment is attriting American naval defenses with cruise missiles and drones, but this is a tall and expensive order. A single CSG has hundreds of interceptors capable of shooting down slower aerial threats. Its radars, unlike the terrestrial ones the Iranians have already destroyed, are mobile. And American naval forces are intentionally operating at the edge of Iranian cruise missile range. The Iranians could expend hundreds of cruise missiles without much to show for it. Perhaps the most realistic possibility for the Iranians to get an edge on American naval forces would be getting a little help from their friends. Chinese and Russian ISR could greatly diminish Iran’s disadvantages in targeting, but it remains to be seen if either state would be willing to take that risk.