The USMC has always had a backup plan. It’s called ‘Super Hornet’.

The US Marine Corps is definitely putting a brave, can-do face on its first unit—Squadron 121—of Joint Strike Fighters (JSFs), aiming shortly for a formal declaration of “initial operating capability.” But Michael Gilmore, the Pentagon’s chief weapons tester, recently penned a dimmer account for procurement chief Frank Kendall. In recent tests on the helicopter carrier Wasp, he wrote, “aircraft reliability was poor enough that it was difficult for the Marines to keep more than two or three of the six embarked jets in a flyable status on any given day.” The Marines have spent billions on the F-35B and the F-35C. Had they not, they might have spent many fewer on the F-18F, and so far, without a noticeable difference.

Last Friday, I covered the question of what the US Navy might have done without a JSF program. In 1992, Defense Secretary Dick Cheney cancelled the Navy’s A-12 carrier-based stealth bomber program, leaving the service without a replacement for its A-6 Intruder and A-7 Corsair II jets. Needing an under-the-radar solution, the service took up McDonnell-Douglas’s idea for a thorough redesign of the F-18C/D Hornet. The result was the F-18E/F Super Hornet, which has sustained carrier air wings in the absence of those long-delayed F-35Cs. The USMC, however, preferred to wait, and never bought into the evolutionary option. So today, the Corps is planning that F-35Bs will replace its long-serving AV-8B Harrier II+s on Wasp and America-class helicopter carriers, and that F-35Cs will replace its aging first- and second-generation F-18A++, -C, and -D Hornets on Nimitz and Ford-class super-carriers.

Fairly, those aircraft may be old, but they’re still capable, at least for now. The latest Harriers today carry the APG-65 active electronically-scanning array (AESA) radar and the long-range, radar-seeking AIM-120 AMRAAM missile. So those six-plane detachments on the smaller flattops, originally meant just for ground attack, can attack enemy flyers too. Before the Harriers, though, the Marines had no jets of any type on assault ships, and no jets capable of operating ashore from austere facilities. In the 1960s and 1970s, the USMC flew F-4 Phantom IIs, and in the Vietnam War almost solely as bombers. The Phantoms flew a tour from the old carrier America, but mostly from the big airfields at Da Nang, Chu Lai, and Nam Phong.

As a marine officer friend of mine once said, if the Marines like something, they call it amphibious, but if they really like it, they call it expeditionary. The Phantom II wasn’t either. The impetus to adopting the Harrier back in the late 1970s was to return to the Corps the rough-field, fixed-wing attack capability that had been lost with the transition to jets. Starting in the 1990s, the F-35B promised to extend that with stealth and supersonic speed. There is also the USMC’s long-running Guadalcanal narrative, in which the Navy once again pulls back the carriers, leaving the Leathernecks exposed on the beach, with just the few F-35Bs of the New Henderson Field to defend them. How well the carefully maintained surfaces of a stealthy aircraft would hold up on those rough fields, however, remains an outstanding question.

But something else has been lost in that second transition. The ongoing complaints about the difficulties of the F-35A and -C as dogfighters were summoned up by the need to make an F-35B. The fat fuselage and the forwarding-looking canopy are artifacts of the placement of the lift-fan directly behind the cockpit. If all-aspect missiles continue to dominate air combat, as John Stillion has shown that they have for decades, then this will not be a problem. Whether advances in electronic warfare could someday challenge that style of war-fighting is yet another outstanding question.

So what would have the Marine Corps have done without the promise of that stealthy jump-jet? Today, the early model F-18s and the AV-8Bs would still be aging out, just like the US Air Force’s A-10Cs, but without a short take-off, vertical-landing (STOVL) replacement. The questions of these replacements are similar, with yet more similar answers: each service intends to replace its (primarily) ground-attack airplane with versions of the F-35. That accomplishes the existing mission for a whole lot more money, as the F-35’s procurement and operating costs will be much higher. The advantage is that the mission should become much easier with the F-35’s networked communications and its APG-81 AESA radar, which tracks not just aircraft, but moving ground targets.

Of course, there’s another plane in the naval inventory with a ground scanning AESA: the F-18E/F with its APG-79. That radar has had a long history of development problems, but as with the JSF, enough money can solve most. The difference is that this is not a whole stealth fighter, but just a radar. Flying the same aircraft with the same radars off the same carriers as the Navy, just as the Corps does today with those F-18Ds, would be rather economical. For that matter, the Marines are even today planning to split their JSF purchases between STOVL Bs and conventionally-landing Cs, the latter operating alongside Navy squadrons on the same decks.

So as a friend at Naval Air Systems Command once told me, HQMC has always had a Plan B behind the F-35B—it just rhymes with “Super Hornet”. In a world without a JSF program, the USMC would likely by now have begun buying F-18Fs to replace its F-18Ds, and perhaps doubled-down on the two-seaters across the fleet. While Goose and Slider would be disappointed to know that the navigator is no longer in style in a fighter, he’s still a valuable observer for close air support. And as the adage goes, it’s understandable that America’s navy needs its own air force, but America’s navy’s army might not need every aspect of an air force.

What that plan wouldn’t have done is keep jet fighters on helicopter carriers, as the F-35B will do. This would have complicated amphibious raids far from friendly bases, to which the Marines need to bring their own over-the-beach air cover. But around the periphery of the Mediterranean, or near the Persian Gulf, the problem is manageable with land-based fighters. And anywhere in the world, no American theater commander would order a full-fledged amphibious assault without massive air cover from the Navy and the USAF.

So after saving those billions that went into their share of JSF development, could the Marines instead have launched the own analog to the Super Hornet? Could they have paid Boeing to design a Harrier III? Certainly, though working from the preceding design, it wouldn’t have been stealthy, fast, or long-ranged. At least one of those is probably crucial in any future fight in the Western Pacific. Could the Marines have gotten that small-ball plan past a defense secretary? That’s much less likely. Advocates of dedicated close air support aircraft have been having a hard time just defending the exiting fleet of A-10Cs. A wholly new Harrier would offer less armor, less payload, and less range. And in Poland last week, the A-10Cs of the 354th proved “they can land anywhere”. Maybe not quite, but that points to the problem. For the United States, the marginal value of the Harrier may always have been something we now call exquisite. And so perhaps, is the F-35B.

James Hasík is a senior fellow at the Brent Scowcroft Center on International Security.