US President-elect Donald Trump is already starting to make his mark on national security and defence.

First, he nit-picked over the costs of building a new fleet of Air Force One planes and called for “greatly” building up the US nuclear arsenal.

More recently, he has complained that Lockheed Martin’s F-35 Joint Strike Fighter (JSF) costs too much, instead requesting that Boeing, manufacturer of the rival F/A-18 fighter, “price out” a “comparable” fighter, based on the F/A-18.

The F/A-18 is a good fighter jet – for certain things. It’s good for flying off carriers and for strike missions, and it’s good for smaller countries that probably cannot afford a state-of-the-art fighter like the JSF. But it is also getting a bit long in the tooth: the latest F/A-18 – the E/F version – has been in production for 20 years.

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If the US military wants to maintain its technological edge against likely future competitors – China and Russia, in particular – then the F/A-18 is probably not the way to go. The F-35 is a “fifth-generation” combat aircraft, meaning it is very stealthy and that it possesses a sophisticated kit of very capable sensors, computers, and software to provide the pilot with a high degree of situational awareness, something called “sensor fusion”.

It is difficult, if not impossible, to make the F/A-18 “comparable” to the JSF. A fourth-generation-plus fighter, it is quite capable, but it cannot replicate the more advanced F-35 in every way. And that is increasingly critical when one considers that both Russia and China are themselves working on next-generation fighters.

The Russians have their PAK-FA fifth-generation prototype, and the Chinese have two fifth-generation fighters, the J-20 and the J-31. If the United States wants to maintain its technological superiority, then it has to have something like the F-35 to keep up.

That said, cancelling the F-35 might have been a good idea ten or 15 years ago. However, for all his talk of being such a great businessman, Trump does not seem to grasp the concept of sunk costs. Almost all the costs for the F-35 up until now – research and development (R&D) and tooling – has already been spent. They are therefore “incurred costs” and cannot be recovered. It would save little to cancel the plane now – in fact, it might cost more, since the government would likely have to pay a penalty for terminating the JSF prematurely.

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Moreover, eight other countries are partnered with the United States on the F-35 programme, and they, along with at least three other countries, are planning to acquire the fighter. To cancel the programme now would be to throw these nations’ force modernisation plans into chaos, and perhaps do irreparable damage to bilateral security relations with the US.

Terminating or cutting back the programme wouldn’t save any money either. Buying fewer F-35s would simply drive up the plane’s total production unit-cost – that is, the cost of each plane, plus the already-spent R&D funding. In addition, with the plane now beginning to enter high-rate production, unit costs are very likely to go way down.

In fact, if Trump wants a more capable fighter jet, he should seriously consider restarting the F-22 programme, which was terminated in 2012 after delivering 187 aircraft. Slightly older than the F-35, it would be (relatively) cheap to upgrade to state-of-the-art standards, and, with a larger payload capacity, it would pack a lot more wallop than the JSF. Countries like Japan, Israel, and Australia would likely be ready customers for this fighter.

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In reality, this is all bluff and bluster. Trump is already committed to drastically increasing the US defence budget. He has called for a 350-ship navy (up from the current 274 ships), a 1,200-fighter air force, and 12 additional marine corp battalions.

At the same time, Trump has to throw some red meat to his government-sceptic voting base. He has to show that he is going to reign in the greed-heads in the military-industrial complex and keep them from gouging the American people. So he sends out a threatening tweet or two, putting the fear of God into the defence industry, who promptly deliver their mea culpas and promise to do better in the future.

The truth is, however, Trump has nowhere to go. Only a few American companies exist anymore that can produce advanced fighter jets, ships, submarines, armoured vehicles, artillery systems and missile systems.

The US defence industry is more segregated from the overall economy than ever before, so finding new suppliers outside the traditional arms industry will be impractical. And Trump is certainly not going to equip the US military with weapons purchased from foreign producers.

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In the end, therefore, Trump’s twitter outrages regarding arms acquisitions are just theatre. He will metaphorically paddle the arms industry, who will be sufficiently contrite, and then it will be back to business as usual. The defence budget is going to soar, the arms industry will get its contracts, and it will be fat city again for the military and its key weapons suppliers.

Richard A. Bitzinger is Senior Fellow and Coordinator of the Military Transformations Programme at the S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University, Singapore.