This month, the U.S. Marine Corps declared that its first squadron of F-35Bs had reached “initial operating capability”. That’s 21 years after the program first began as the Joint Advanced Strike Technology (JAST) program, 18 years after the first Joint Strike Fighter (JSF) design contracts were awarded, and yet 13 years after Lockheed Martin won the development contract for the F-35 Lightning II, way back in October 2001. It’s notable that a war started the month prior to that award. Perhaps it’s intriguing to ask what might have happened if that contract had never been signed—if, perhaps, the Pentagon had gone all-in supporting the fighting in Afghanistan (and later Iraq), and found some other solution for backfilling its aging fighter fleets.

Other defense ministries have pursued other ideas, but with comparable programmatics. The Typhoon was similarly in development for 20 years before its entry into service in 2003. Recently, the Business Standard of India reported that Eurofighter GmbH has managed to reduce the unit production cost of its jets by 20 percent over the past five years, even while reducing the production rate (HT: DID). That would constitute a considerable discount on the £87 million ($135 million) that the British National Audit Office recently estimated that the average aircraft has cost throughout the program.

Extrapolating a little from the Selected Acquisition Report of December 2014, the U.S. Defense Department alone has so far spent or appropriated just under $100 billion on its F-35s. Over half of that has been for development and construction; only about $45 billion has gone into low-rate initial production of the first 300 or so aircraft. The production cost of a Lightning is thus not wickedly worse than that of a Typhoon, though Dassault’s Rafale is probably a bit less. Boeing’s Super Hornets and Saab’s Gripens cost much less—perhaps only half as much, depending on the basis of the estimate.

What else might the Pentagon done with that $100 billion? (Apart, of course, from the Treasury not borrowing it in the first place!) Forgoing new development, the whole sum would have bought about 740 Typhoons, or 1300 Super Hornets—and those aircraft would be in service already. As the F-35 is only now just available, the wars in Afghanistan and Iraq would have gone no worse. The Navy would have no carrier deck shortfall. No one would be anguishing over the decaying state of the fighter force. Chinese Intelligence would have had no new stealth fighter plans to steal. So the dreaded Chengdu J-20, like the much-ballyhooed Sukhoi PAK-FA, would still be just a prototype. And this would all be well-and-good, for now.

For by the threat estimates on their briefing slides, a grim mood would have already set in amongst the air admirals and generals. Enemy aircraft aren’t the stressing threat yet; it’s enemy missiles. Those “fourth-generation” fighters (as Lockheed’s marketing literature calls them) are expected to suffer high loss rates against Almaz-Antei’s S-300 and S-400 anti-aircraft batteries, now in service from Russia to China to Syria, and maybe soon in Iran. Squadrons of Super Hornets could attempt to fly through them, much like B-17s weathering flak over Schweinfurt. The other frightening missiles are China's legions of the anti-ship variety, on aircraft, ships, and trucks. China’s latest aircraft, too, aren’t to be trifled with. As I heard a retired air admiral put it recently, "with squadrons of J-20s coming eastbound, a supercarrier in the China Seas might need all 44 of those F-18s just to defend itself.” Either way, such a “grinding strategy of attrition,” as Max Boot pointed out back in 2003, no longer fits in what Russell Weigley once termed “the American War of War”.

Against this threat, but without the F-35C, the U.S. Navy might have gone long. (I’ll cover other buyers next week.) Speaking at the Citadel in 1999, Texas governor George Bush argued that “our relative peace”—seemingly now lost—was going to allow a fundamental restructuring of the U.S. armed forces, in which Pentagon buyers could “skip a generation of technology”. Just which generation remains a fair question. Citing that speech in 2001, Ivan Eland of the Cato Institute argued for skipping the F-18 and the presumably “fifth-generation” F-22 in favor of the newer F-35. In Naval Institute Proceedings that year, I argued for skipping the F-22 for the F-18 and the F-35. Without an F-35, the airplane Secretary Mabus calls “almost certainly… the last manned strike fighter,” the Navy might have gone straight for that “sixth-generation” of the unmanned. The Navy might have put mad money on really long-range drones, to restore the striking range that the fleet lost with the retirement of the A-6 Intruder in 1997.

There’s reason to think that this would have produced some impressive robotic aircraft. In 1994, when the JSF was getting underway as the JAST, General Atomics was under contract with DARPA to demonstrate the MQ-1 Predator. The next year, it was flying reconnaissance over Bosnia. In 1999, NATO lost thirty drones over Yugoslavia—a loss that would have been alarming had the aircraft been manned. In 2001, the Predators were firing missiles over Afghanistan. By 2007, turboprop MQ-9 Reapers were taking their place. The next year, the 138th Attack Squadron of the New York Air Guard became the first unit to trade in its fighters for drones. Sometime around then, Lockheed Martin brought out its RQ-170 Sentinel, the ‘Beast of Kandahar’, to scout over Pakistan for ObL. Sometime around then, Northrop Grumman worked up its presumably larger and longer-range RQ-180. In 2014, that company showed that its X-47Bs could take off from carriers, refuel in the air, and then land on those carriers.

Think about how much more could have been accomplished with just a part of that hundred billion dollars. In the meantime, the Marines have declared IOC with that JSF.

James Hasík is a senior fellow at the Brent Scowcroft Center on International Security at the Atlantic Council where this piece first appeared.