USS Abraham Lincoln in the Iran War

Despite all these layers of defenses, the American CSGs in the theater have been extremely cautious. The CSGs themselves loiter cautiously behind an invisible barrier 150 nautical miles (278 km) from the Iranian coast, rarely venturing beyond it. The distance is telling. Allow perhaps 30 kilometers between the coast and a plausible launcher position, and the CSGs sit just beyond the reach of most Iranian ASCMs. This shows they take the threat seriously, but it allows them to continue to sortie aircraft to strike Iran.

(there's a map of the Lincoln's coordinates here that I can't really embed since it's not just a plain image file, so you might want to open up the article to check it)

Iran's Anti-Ship Ballistic Missiles

Astute readers will be asking, “Ok, but what about Iranian anti-ship ballistic missiles?” Because, indeed, Iran has fielded ASBMs, and Ansar Allah has verifiably used them in combat. The most well-known of these systems is what Ansar Allah refers to as the Asef, which is believed to be based on the Iranian Khalij Fars (literally “Persian Gulf”). This missile supposedly has a 500 kg warhead, a 400 km range, and satellite-supplemented inertial guidance with an electro-optical terminal seeker. Ansar Allah used the Asef, or a similar system, to target at least 19 commercial shipping vessels from 2023 to the present. The track record is mixed, with several hits, many misses, and perhaps one vessel sunk, though it isn’t clear if an ASBM was used in that case. Based on the heritage of these systems, there’s little reason to expect them to enjoy the same advantages as Iran’s most advanced medium-range missiles, and they don’t present evidence that Iran has solved the fundamental problems in ASBM design. The publicly stated range of these systems suggests they have the profile of a short-range ballistic missile (SRBM), and the accordingly lower speeds of short-range ballistic systems. There’s no evidence they can perform complex evasive maneuvers while still hitting their target, which is itself moving.** The profile of their trajectory is unknown. They may have trouble dealing with the evasive maneuvers that satellite imagery shows American ships performing.

Recipe for Success

The winning recipe for defeating modern air defense systems, based on the performance of Iranian MRBMs, looks something like this: The missile should be fast. Ideally, it would have a high impact speed, or a terminal boost capability like the Fattah-1, allowing it to accelerate (over Mach 5 at least) during the terminal phase to offset aerodynamic drag. It should be capable of performing evasive maneuvers and have a quasi-ballistic trajectory. And it should have a long range to put opposing naval forces within reach. The trick is designing a system with this profile that’s also capable of hitting a moving target, and the specific moving target intended. But the constraints here appear near-insurmountable. Electro-optical seekers fail within a plasma sheath. A projectile traveling at high-hypersonic speeds has almost no time to adjust its trajectory to track a target that may have moved kilometers during flight.

Legenda

One of the key answers to solving this problem is continuous, real-time, external ISR. The Soviets understood this as early as the 1960s, and began developing the Legenda satellite constellation in response. Legenda was extraordinarily ambitious. It would comprise a constellation of dozens of nuclear-powered radar and SIGINT satellites. The nuclear-powered component was necessary so the radar satellites could maintain an exceptionally low orbit—necessary for active radars in space—with regular reboosts. The satellites would provide worldwide coverage for tracking the exact position of naval targets. They would interface with the launch systems of the P-700 Granit (NATO: “Shipwreck”), the most massive (7,000 kg) anti-ship cruise missile ever fielded, which would be capable of ramjet-powered supersonic speeds exceeding Mach 2.5. The Granit would be launched in large swarms of dozens of missiles, with a lead missile with an active radar seeker flying above the rest and communicating the live position of the target via datalink. If that missile were shot down, another would take over.

This was the first true end-to-end aircraft carrier kill chain, with every component designed from the ground up to destroy an American CSG specifically. The Soviets were the only power on earth with the resources and motivation to deploy the world’s first (nuclear powered!) dedicated naval ISR satellite constellation. But the Granit wasn’t fielded until 1983, and the full Legenda constellation wasn’t deployed until 1988. The program faced massive technical challenges and multiple major setbacks, which is unsurprising considering its complexity and ambition. Gorbachev cancelled it the same year the last satellite in the constellation was launched, and Legenda was already heavily degraded by the time the USSR collapsed in 1991. Legenda also lacked what we’ve already identified as the silver bullet for overcoming air defenses: an extremely fast, highly accurate anti-ship ballistic missile.

East Wind

The only nation that can make a plausible claim (emphasis on claim here) to having solved all the problems outlined above is China, which is unsurprising given that, just like the Soviets, they have both the resources and the motivation to push the state of the art forward in this area. Studying Chinese ASBM development can inform our analysis of Iranian efforts. The Chinese have launched hundreds of ISR satellites into orbit, with their total in orbit increasing by a factor of six from 2018 to 2026. These include what are speculated to be dedicated constellations just for tracking American aircraft carriers. The scale of these constellations dwarfs Legenda’s, which could only provide short windows of active radar tracking. And crucially, the Chinese claim to have developed geostationary synthetic-aperture radar ISR satellites that allow uninterrupted tracking of an individual target, which is otherwise impossible given the narrow viewing window of SAR. Combined with over-the-horizon radar, ship-based radar, and AWACS, it’s plausible to say that the Chinese are capable of knowing the precise location of an American aircraft carrier in the Pacific for lengthy, uninterrupted periods, or perhaps at all times. This is the first major problem to solve in developing a true carrier killer.

The Chinese fielded the first operational ASBM in history, the DF-21D, in 2010. Because the DF-21D has never been used in combat, and its specifications are classified, we can only speculate on how closely its claimed capabilities match reality. But its general profile is thought to be a maneuvering MRBM with a very low (estimates are 20 m) CEP, a terminal phase active radar seeker, and a 1500 km range. The DF-21D is commonly cited as having a Mach 10 “terminal phase,” though this is likely its speed at atmospheric re-entry. In order for the active radar seeker to function, it probably slows down significantly, to around Mach 2, before impact. This is how the American Pershing II IRBM worked, engaging in a “pull up” maneuver so its active radar seeker could compare the ground below it against preloaded terrain maps. The Chinese have developed a succession of more advanced anti-ship systems since the DF-21D was introduced in 2010 (be warned, the following information is highly speculative). The DF-26 is an IRBM that builds on the DF-21D with nuclear capability and increased range. The Chinese have tested it against full-scale (non-moving) mockups of Gerald R. Ford-class carriers and Arleigh Burke-class destroyers. The YJ-20, a naval-launched, hypersonic ASBM, appeared in 2025. Its biconic design should theoretically allow much higher terminal speeds and greater maneuverability than a traditional blunt cone reentry vehicle. Also of note are Chinese hypersonic glide vehicles (HGVs), of which it has fielded at least three. An HGV moves in a flat trajectory while skipping along the atmosphere. They trade raw speed at impact for maneuverability, and various militaries claim they’re capable of extreme maneuvers that would never be possible with a traditional missile design. Their trajectory makes them immune to high altitude defense systems like the THAAD and Arrow-3. The open question is whether any of these is truly capable of active terminal guidance against a moving target. There’s no real evidence they are, and even so, an HGV doesn’t necessarily impact its target at high Mach, making it theoretically possible for it to actively seek a target, but also feasible to intercept.

While it’s reasonable to assume that HGVs will defeat high-altitude naval defenses like the SM-3, which has a minimum intercept altitude around 100 km, lower-tier interceptors may still pose a threat to them. The high terminal speed/maneuverability combination that’s made Iranian missiles so deadly may not have an ASM equivalent due to the complexities involved in designing an active seeker that can function at high Mach. There’s little public information on the state of the art in high-Mach seekers. The Iranians themselves appear to be pushing the envelope here and claim the Qassem Bassir, arguably the most advanced Iranian MRBM, is equipped with an infrared electro-optical seeker that functions at speeds greater than Mach 5, giving the system “meter-level” accuracy. But this is supposedly a scene-matching system designed for use against static land targets, freeing it from the constraints that make ASBMs so challenging to design. And there’s no evidence yet of the Mach 5 impact claim.